Kahlenberg, Georg. “Datenhandbuch, Band II: State, Economy and Society in WesternEurope 1915-1975. A Data Handbook, Band II: The Growth of Lndustrial Societies and Capitalist Economies”. Wirtschaft Und Gesellschaft, vol. 14, no. 1, Jan. 1988, pp. 173-4, https://journals.akwien.at/index.php/wug/article/view/1201.