An Overview of the World Crisis and International Trade

Johnson, Harry G. Article An Overview of the World Crisis and International Trade Kredit und Kapital Provided in Cooperation with: Duncker & Humblot, Berlin Suggested Citation: Johnson, Harry G. (1975) : An Overview of the World Crisis and International Trade, Kredit und Kapital, ISSN 0023-4591, Duncker & Humblot, Berlin, Vol. 8, Iss. 4, pp. 433-449, https://doi.org/10.3790/ccm.8.4.433 This Version is available at: https://hdl.handle.net/10419/292747 Standard-Nutzungsbedingungen: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Terms of use: Documents in EconStor may be saved and copied for your personal and scholarly purposes. You are not to copy documents for public or commercial purposes, to exhibit the documents publicly, to make them publicly available on the internet, or to distribute or otherwise use the documents in public. If the documents have been made available under an Open Content Licence (especially Creative Commons Licences), you may exercise further usage rights as specified in the indicated licence. https://creativecommons.org/licenses/by/4.0/ An Overview of the World Crisis and International Trade By Harry G. Johnson, Chicago, 111. It is extremely difficult, even for those who were already mature and established economic adults at the time, how settled, stable, and virtually automatically growing in terms of productivity, technological improvement, and individual standards of living the world economy seemed to be as little as a decade ago. Employment was normally at levels in excess of the "full employment" standard of the earlier part of the century. Productivity — even in Britain, the "sick man" of Europe — was rising at a rate well in excess of any recent sustained experience. And all this, was occuring consistently with rates of price increase of a few percent per annum, close to the statistical margin of error in price indexes and the "threshold of sensitivity" of public concern about inflation; and with a steady reduction of barriers to international trade and investment (excluding the special case of agricultural protectionism). It is true, that the international monetary system of fixed rates of foreign exchange based on the use of the U. S. dollar as the world's reserve currency was showing signs of strain. But there was ample confidence among the advanced countries that a new system based on an international credit-based reserve money, and providing somewhat more flexibility of exchange rate adjustment, would be evolved by international agreement in due course and in good time. So far as the lessdeveloped "third world" was concerned, the errors of excessive inwardlooking protectionism were coming to be recognized, as was the necessity of shifting the emphasis of development policy from industrialization to increasing agricultural productivity. Meanwhile, the "green revolution" held out the hope of a solution to the population problem through the development of acceptable programs of population control being reached before the "classical checks" of starvation and misery came inexorably into play on a serious scale. How the world has changed in the intervening decade! The spectre of famine in a number of the less developed countries has again raised 28 Kredit und Kapital 4/1975 OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 434 Harry G. Johnson its ominous head. While this is not my main theme, it is worth noting that the humanitarians have as usual confused the problem of shortage of food with shortage of resources in general; and that an important part of the problem is inefficient transport systems and indifference about or ineffectiveness in dealing with the problem of domestic food distribution on the part of the governments and governing classes of the less developed countries themselves. Nevertheless, there are obvious connections between the current food problems of certain less developed countries, and the more general problems of inflation, recession, and escalated oil prices and energy disturbance. Oil for many such countries seems more vital to the future than food itself. And certain self-centred anti-inflation policies in the developed countries have tended to disrupt the production and interfere with the sharing through international trade of potentially available food supplies. The matter of more general concern is that inflation on a world basis has escalated well into the two-digit range, while at the same time the trend of unemployment has been upward, culminating recently in the appearance of some strong signs, and of even stronger fears, of a major world depression. The process of escalating inflation has been dramatized by the collapse of the fixed exchange rate system in February, 1973, and the adoption of a floating exchange rate system rightly characterized at least in its early stages as "a regime of dirty floating". In spite of some of the common arguments for floating rates as a safety valve for inflation, what is generally referred to as a world inflation has continued on its merry and ever-magnifying way. More accurately, precisely because of widespread misunderstanding of what a floating rate system can and cannot do, and particularly of the dependence of what a floating rate does on what overall fiscal and monetary policy the national governments choose to follow, floating exchange rates have not only not been used to combat inflation, but have instead been used in some countries at least to permit inflation to accelerate while absolving governments from responsibility for it. In the meantime, both the superior ability of floating rates to cope with international monetary and financial problems, and continuing inflation and more recently the energy crisis, have relegated to limbo (or to purgatory, if you will) the determination to restore a fixed exchange rate system sufficiently improved to survive and flourish for the rest of the century. As if the problem of "stagflation" — as it came despairingly to be called, in the days when people still did not know first-hand what a OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 An Overview of the World Crisis and International Trade 435 real problem of large-scale industrial unemployment was — were not enough to struggle with, the difficulties and the gloom have been vastly increased by the four-fold rise in the price of oil initiated in the winter of 1973 - 74. Adding to the difficulties associated with the increase in the oil price by itself have been the resulting uncertainties about the reliability of future supplies, the financing of oil deficits and surpluses, and the energy and balance-of-payments policies of the major nonO.P.E.C. oil-consuming and -producing countries; and more generally, uncertainties about the survival of a liberal world trade order. It is little wonder, then, that public opinion has rapidly come to think of the 1960s, or the late fifties and early sixties, as a sort of "golden age" unlikely to be experienced again. Some pessimists indeed are prepared to assert that the decline and fall of western European civilization has already got under way, and to envisage with resignation an inevitable collapse into barbarism. Others, more sanguine and usually younger, foresee nothing but continuing difficulties, summarized in the concepts of secular inflation, another "great depression", and a growing scarcity of energy requiring the transformation of the planet into a space-ship economy and ecology. To understand the problem of recent world inflation it is I believe most illuminating to see the problem in the context of ignorant management, or deliberate mismanagement, of a system of fixed exchange rates such as the gold standard, which standard has broadly prevailed, with gradual modifications, and occasional disruption, up until 1973. Such a standard, as has often been said, imposes an automatic monetary discipline on the member countries of the system, through the need to maintain balance-of-payments equilibrium at the chosen exchange rate. But, contrary to the beliefs and assertions of its advocates, the system imposes no pressure whatsoever for the maintenance of stable prices in the world economy. Instead, it imposes strong pressures on each and every member country to keep in step with the world rate of inflation or deflation. That rate, in turn, is determined in broad terms by the growth of the supply of international reserves on the one hand; and on the other hand by the growth of the demand for such reserves, as determined by general economic growth and by financial innovations economizing on the international reserves needed to back domestic money supplies and the use of credit in international payments. Reference to the use of credit in substitution for actual reserves points to the Achilles heel of the system. Not only does the use of credit in place of 28* OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 436 Harry G. Johnson actual money depend on confidence which can be shattered and lead to an international liquidity crisis, but there is always economic pressure for such substitution because gold is sterile, requiring real resources to mine and yielding no interest on the resulting asset, and paper money costs nothing to create and can be invested in productive assets. Further, at least until the invention of Special Drawing Rights and most likely even since, the credit money substitute is inevitably a national currency, and its use is conditioned by the state of general confidence in the nation whose currency is so favoured. Thus Britain in the 1920s was unable to restore the role and leadership of the pound sterling in the actual functioning of the gold standard ("the gold exchange standard", as it has come more accurately to be termed); and European national rivalries combined with American isolationism and monetary mismanagement to produce the international collapse of the 1930s. As a result of that experience, international monetary thinking, as embodied concretely in the International Monetary Fund, started unconsciously from the assumption that a shortage of international liquidity was the chronic weakness of a fixed rate system, and mass unemployment of the 1930s variety the major problem to be solved by economic policy. But this assumption overlooked the fact that the fixed rate system (like any well-conceived and logical system) is itself neutral, and simply serves to channel either deflationary or inflationary disturbances through the world economy in a certain orderly way. Thus, in an important sense, what we have been having in the past decade has been a "re-run in reverse" of the 1930s — with a world inflation instead of a world deflation; with the weakness of United States monetary policy the main source of disturbance; with the European countries unable to agree on the concerted policy action that would either have solved the problem globally or isolated the United States to bear the full costs of its own policies of monetary mismanagement, without infecting others; and with the system eventually collapsing under the strain of its own inner contradictions into a regime of dirty floating of exchange rates. We can, at this date, even carry the parallel one stage further. For in the 1930s, as in the 1970s, countries did not in fact use the freedom of a floating exchange rate to pursue boldly independent economic policies — at that time of economic recovery and full employment — but instead attempted to maintain traditional or modifiedtraditional relationships between the values of the domestic and foreign currencies, eventually winding up at pretty much the same exchange OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 An Overview of the World Crisis and International Trade 437 rate relationships as they had started from. In fact, the main international monetary accomplishment of the travail and suffering of the 1930s was to remedy the international liquidity shortage by raising the price of gold; and if one likes to play with historical analogies, one might ponder the thought that the main effects of world inflation and dirty floating in the 1970s will eventually come to be seen as a roundabout and inefficient means of mopping up excess world liquidity in the form of surplus United States dollars. This remark, however, takes us somewhat ahead of the main story. For roughly two decades, the restored gold exchange standard worked surprisingly well, partly perhaps because inflationary policies can be used to support high employment without fomenting actual inflation so long as the public continues to believe that stable or falling prices are the historical norm. To be more precise and technical, the system worked well largely because, by luck rather than conscious management, the United States maintained reasonably stable prices, while by virtue of the dominance of the United States in the system other countries could remedy inflationary errors or policies by devaluing against the dollar from time to time, on an individual basis which left intact the concept of a fixed exchange rate system. It is true that there were, increasingly from the end of the 1950s on, manifestations of resentment against the presumed unique advantages accruing to the United States by virtue of the reserve currency role of the dollar. But this resentment was directed against the presumed advantage of "dollar imperialism" and relative freedom from balance-of-payments disciplinary urgency, not against the potential or actual power of the United States to force inflation on the rest of the world; and in any case by the mid-1960s the major European central bankers had more or less accepted the idea that the United States was confronted with special problems but was doing its best under the circumstances. All this changed with the failure of the United States to accompany the escalation of the war in Viet Nam by appropriate tax increases, and its reliance on monetary expansion instead — together with a subsequent general laxity of American monetary policy the reasons for which have been too complicated to enter on here. As mentioned, a sustained inflation, in a reserve currency country especially, must spread itself throughout the fixed-rate system; the only escape available for the others is through either floatation of exchange rates, or frequent and co-ordinated currency revaluation against the inflating country. But the OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 438 Harry G. Johnson European countries were conditioned to think of exchange rate adjustments as being directed against their European neighbours, though expressed in terms of the dollar exchange rate, rather than directed against the United States by European neighbourly cooperation. Further, the standard theory of anti-inflationary policy, which was strongly influenced by both war and immediate postwar economic management experience and by Keynesian policy theories that assumed a closed national economy and a sociologically-determined level of money wages, persistently envisaged inflation as a national problem, to be dealt with by national fiscal and monetary policies, supplemented by a national wage-price policy. Consequently, much time and ingenuity was wasted in denying the obvious and devising brilliant improvisations on the irrelevant, with the ultimate aim and result of avoiding necessary exchange rate changes at the expense of willy-nilly enduring unnecessary inflation — until President Nixon's "New Economic Policy" of August 1971 cut the Gordian knot and allowed the Europeans sufficient rope to hang themselves in their own inability to agree on a collective worldresponsible solution. It was during this period — towards the end of the 1960s — that the actuality and the concept of "stagflation" began to surface in European and American policy discussions. If European and American policymakers and economists were not so parochial, they would have recognized the problem as a familiar one in Latin American experience. "Stagflation" means the combination of unusually high unemployment with abnormal rates of inflation or even accelerating inflation. It is an artificial word, of the kind that British journalists love to coin and their academic and official readers to circulate ostentatiously, under the false impression that to coin a new word is to prove the existence of a new problem that confounds all established theory and clears the way for the novel theory of the semantic counterfeiter himself. The reality of "stagflation", however, did deal an almost mortal blow to the selfconfidence of the Keynesian school of economic policy thinkers. The reason was that, on the basis of an erroneous theory that followed Keynesian tradition in confusing real and money wages, contemporary Keynesian theorists had espoused an alleged empirical relationship called "the Phillips curve". According to that theory, the rate of inflation of money wages is determined by the balance of real demand for and supply of labour, summarizable in the unemployment rate, such that society has a "trade-off" between the rate of unemployment and the OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 An Overview of the World Crisis and International Trade 439 rate of wage and price inflation it can have. The appearance of continuing inflation and rising unemployment appeared to destroy the heart of Keynesianism as a theory of economic policy. In fact, what it should have — and subsequently has — destroyed is the simple notion that workers and employers are blissfully ignorant of the fact that inflation is going on, and happily settle for the same money wage increases as usual, despite the obvious effects of inflation in reducing the real value of a given money wage increase to the workers and its real cost to employers. Still, as my great teacher Joseph Schumpeter used to tell his classes in the history of economic thought: "When an economist finds his predictions flatly contradicted by the evidence, he never says 'I am a fool!' Instead, he says 'Reality is much more complicated than even I had thought." The appearance of the phenomenon of "stagflation" is easy enough to understand, once one clears his mind of the Keynesian assumption that a nation is a closed economy, or closed partially, in the sense that foreign influences can only affect it through the income-multiplier and international reserve flow effects of the balance of payments, and that workers and employers are too stupid to recognize an inflation when it hits them in the face. Let me list the main points of explanation without attempting to be comprehensive. First, under a fixed exchange rate system, as already mentioned, all members are inexorably doomed to more or less the same rate of inflation, due allowance being made for leads, lags, and national differences between the movements of measured price indices in different countries experiencing the same basic inflationary impetus. An important implication is that the national rate of inflation may have little or no connection with the state of the national labour markets. In the extreme, countries may have not even a short-run employment-inflation trade-off, and only a choice of how much unemployment to suffer along with the world rate of inflation. To be more pointed, if countries wrongly believe that they can trade off domestic unemployment for a lower world inflation rate, they can get the higher unemployment, but they will not get the abatement of inflation: in other words, their policies will create "stagflation", confounding their Keynesian economists and policymakers. Second, nothing but confusion can result from the usual political procedure of selecting a certain magic number as a full-employment target, by psychic bidding for electoral support. Apart altogether from OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 440 Harry G. Johnson the likely effect of uncertainty bred by inflation, in making both workers and employers more willing to stay out of the labour market temporarily in hopes of an eventually more satisfactory and betterinformed contractual employment commitment, the "normal unemployment rate" consistent with price stability is itself an economic variable, and one subject to policy influence. It is frequently ignored that the 1930s crash led to the development of two alternative lines of policy attack on the evils of depression: full employment policy, to be implemented by Keynesian demand management; and social insurance and social security provisions, designed to remove the social and personal economic sting of unemployment and related income-loss problems. To the extent that the provision of social security has been successful — and it may well have been all too successful for the majority of the population — it obviously increases the limit points of numbers and duration of unemployment beyond which unemployment is an objectively serious social problem. Further, the progress of affluence, including increased female participation in the labour force, has had a significant parallel effect by spreading the risks of unemployment over the accumulated capital as well as the labour-power of the typical worker, and over more than one worker in the family unit. Thirdly, since the population of the major advanced cuuntries entered the recent inflationary period with two centuries of experience of price stability in peace-time, and changing society's views of normality is a slow process, one should expect people to go on for a long time after inflation has once got under way, making their decisions on the assumption of continuing inflation even though they personally are suffering from deflation (specifically, unemployment). After all, it took nearly a quarter of a century after the second world war for inflation to build up into a normal way of life in the countries that had suffered mass unemployment in the 1930s; and it would be surprising indeed if governments, simply by announcing their determination to stop inflation, could turn public opinion around within the six-months-to-a-year-or-so period which is the maximum span of attention that either the public or its government can devote to pursuing a logical but unpopular policy. Hence one has the worst of all possible results: all the misery of trying to stop inflation and none of the satisfaction of succeeding. This is, of course, the main fear of those who foresee continuing rapid inflation ahead — not that governments could not stop inflation if they really tried, but that the need for re-election will always lead them to OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 An Overview of the World Crisis and International Trade 447 ments from the impact of inflation and the oil crisis. The liberal order of international trading arrangements has been infringed on in some important ways. But its main contours still stand; and while they do, they continue to offer the opportunity of economic growth and development through international trade and specialization. Zusammenfassung Ein Überblick über die Weltwirtschaftskrise Gegenstand der Untersuchung sind die Gründe für die weltweite Krise und ihre Rückwirkungen auf den internationalen Handel. Eine zentrale Stellung nimmt dabei die Frage ein, wie es zu dem Zusammentreffen von Inflation und Unterbeschäftigung kommen konnte — und dies in einer Welt, die durch die Aufgabe fixer Wechselkurse inzwischen die Möglichkeit hat, sich gegen inflatorische Einflüsse aus dem Ausland zu schützen. Einleitend wird zunächst klargestellt, daß auch der Gold-Devisenstandard und das mit ihm verbundene System fester Wechselkurse keinen Zwang zur Stabilität ausübte, sondern lediglich einen gewissen Gleichschritt in den Inflationsraten verlangte. Aber auch ein System floatender Wechselkurse sichert nicht gegen inflatorische Störungen, wenn es sich überwiegend um ein „schmutziges Floaten" handelt. Hinzu kommt die Tendenz der Notenbanken, sich auch in einem System frei schwankender Kurse wie unter der Herrschaft fester Wechselkurse zu verhalten, da sie vornehmlich auf die Veränderungen der Kurse gegenüber ihren Nachbarländern achten. Hauptquelle der Weltinflation war die Tatsache, daß die Vereinigten Staaten es versäumt haben, den Vietnamkrieg über Steuererhöhungen zu finanzieren. Die Überproduktion an Dollar mußte sich bei festen Wechselkursen über die ganze Welt ausbreiten. Dieser inflatorische Effekt ist erst durch die substantielle Abwertung des Dollars gemildert worden. Die europäischen Länder haben jedoch den ihnen durch die Maßnahmen von August 1971 eingeräumten Spielraum stabilitätspolitisch nicht genutzt. Die Möglichkeit zur Überwindung der Weltinflation wird vor allem aus der veränderten Haltung der amerikanischen Administration zur Inflation und aus dem Umstand abgeleitet, daß damit wieder ein dämpfender Einfluß auf andere Länder ausgeübt wird. Die Untersuchung schließt mit einigen Überlegungen zum Einfluß der Ölkrise auf die Inflation. Es wird gezeigt, daß dieser Einfluß begrenzt gewesen wäre, wenn man diesem Problem mit den Erkenntnissen aus der Kartelltheorie und -praxis begegnet wäre. Erst der Versuch, den Folgen der ölpreiserhöhungen durch Subventionen zu begegnen, hat ihren preistreibenden Einfluß verstärkt. OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 448 Harry G. Johnson Summary An Overview of the World Crisis and International Trade The subject of this study is the grounds for the worldwide crisis and their repercussions on international trade. Central importance is assigned to the question of how it was possible for inflation and underemployment to coincide — and that in a world which, through giving up fixed exchange rates, is meanwhile capable of protecting itself against inflationary influence from abroad. In the introduction, it is first made clear that the gold exchange standard, too, and the related system of fixed exchange rates, exerted no compulsion to preserve stability, but merely demanded a certain degree of uniformity of inflation rates. But even a system of floating exchange rates is no safeguard against inflationary disturbances, if the floating is predominantly of the "dirty" type. An additional facet is the tendency of central banks to behave in a system of freely fluctuation exchange rates in the same way as when fixed exchange rates prevail, since their attention is focused primarily on exchange rate changes relative to their neighbouring countries. The chief source of world inflation was the fact that the United States failed to finance the Vietnam war by tax increases. With exchange rates fixed, the overproduction of dollars necessarily had to spread over the whole world. This inflationary effect was ameliorated only by the substantial devaluation of the dollar. The European countries, however, did not take full advantage for stabilization policy of the latitude they were given by the measures of August 1971. The possibility of overcoming world inflation is derived above all from the changed attitude of the American administration to inflation and from the circumstance that this will exert a damping effect on other countries. The study concludes with thoughts on the influence of the oil crisis on inflation. It is shown that this influence would have been limited, if this problem had been tackled with the knowledge from cartel theory and practice. It was not until the attempt was made to combat the consequences of oil price increases with subsidies that its price-raising influence was strengthened. Résumé Un survol de la crise économique mondiale L'article a pour object de rechercher les causes de la crise universelle et ses effets sur le commerce international. D'importance primordiale est la question de savoir comment ont pu se conjuguer l'inflation et le sous-emploi, en particulier dans un monde où, par l'abandon des cours fixes de change, l'on avait la possibilité de se protéger des influences inflationnistes en provenance de l'étranger. OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32 An Overview of the World Crisis and International Trade 449 Il est d'abord établi dans l'introduction que l'étalon-or de change et le système de taux fixes de change qui s'y rattache n'exercent pas de contrainte vers la stabilité; ils requièrent uniquement une certaine symétrie entre les taux d'inflation. Mais un système de changes flottants n'offre pas non plus de garantie contre les perturbations inflatoires dès lors que l'on a principalement affaire à un « ottement malsain ». Et il faut encore ajouter que la tendance des banques centrales est de se comporter dans un système de taux flottant librement comme sous l'empire de cours fixes, car elles surveillent principalement les modifications de taux à l'égard des pays voisins. La source principale de l'inflation mondiale fut le fait pour les Etats-Unis de négliger de financer la guerre du Vietnam par des augmentations d'impôts. La surproduction de dollars devait par le système des taux de change fixes se répandre à travers le monde entier. Cet effet inflationniste ne s'est réduit qu'à dater de la dévaluation substantielle du dollar. Les pays européens n'ont cependant pas exploité en faveur d'une politique de stabilisation la liberté de manoeuvre que leur octroyaient les mesures du mois d'août 1971. La possibilité de maîtriser l'inflation mondiale est surtout basée sur un changement de mentalité de l'administration américaine, ce qui aurait des répercussions de freinage dans d'autres pays. L'étude s'achève sur quelques considérations relatives à l'influence de la crise pétrolière sur l'inflation. L'auteur souligne que cette influence aurait pu être limitée si l'on avait abordé le problème par le biais de la science théorique et pratique des cartels. Mais la tentative de contrecarrer par des subventions les effets du renchérissement du pétrole n'a servi qu'à renforcer leur tendance à hausser les prix. OPEN ACCESS | Licensed under CC BY 4.0 | https://creativecommons.org/about/cclicenses/ DOI https://doi.org/10.3790/ccm.8.4.433 | Generated on 2023-01-16 13:32:32