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↑ Smith, Adam: An Inquiry into the Nature And Causes of the Wealth of Nations Book 2 – Of the Nature, Accumulation, and Employment of Stock; Published 1776.
↑ Caves, R. W. (2004). Encyclopedia of the City. Routledge. tr. 362. ISBN9780415252256.
↑ The Forms of Capital: English version published 1986 in J.G. Richardson's Handbook for Theory and Research for the Sociology of Education, pp. 241–258.