To recall all those who have contributed to the genesis of the present work involves pleasant reminiscence. The grey skies of Belgium come to mind with the acknowledgment that without the aid of two United States Government (Fulbright) Grants the study would have been stillborn. Both Dorothy Deflandre, Executive Officer of the U.S. Educational Foundation in Belgium, and Henri Janne, then Director of the Institut de Sociologie Solvay, used their official powers to facilitate the process of research. Another scene, equally impressed upon the memory - the placid setting of Amsterdam's Keizersgracht - arises with therecollectionofthe courtesy of the Internationaal Instituut voor Soci ale Geschiedenis, whose director, the late A.J.C. Rüter, kindly granted me access to the de Man archives. I take pleasure also in acknowledging financial support from the Research Foundation of the State University of New York, whereby I could investigate further materials later made available at the Archives Generales du Royaume in Brussels.

Annually published since 1930, the International bibliography of Historical Sciences (IBOHS) is an international bibliography of the most important historical monographs and periodical articles published throughout the world, which deal with history from the earliest to the most recent times. The works are arranged systematically according to period, region or historical discipline, and within this classification alphabetically. The bibliography contains a geographical index and indexes of persons and authors.

Volume 40C of Research in the History of Economic Thought and Methodology features a symposium on the work of economist François Perroux, edited by Katia Caldari and Alexandre Mendes Cunha with collected book reviews of David M. Levy and Sandra J. Peart’s (2020) Towards an Economics of Natural Equals.