1. Allen, Robert L. (1991). Opening Doors. The Life and Work of Joseph Schumpeter, Vol. 1: Europe, Transaction Publishers, New Brunswick, N.J., pp. 96–102.
2. Balabkins, Nicholas W. (1988). “Schmoller in Tsarist Russia.” Journal of Institutional and Theoretical Economics (JITE), Vol. 144, pp. 584–585.
3. Borchardt, Knut (1961). “Albert Schäffle als Wirtscahftstheoretiker.” Zeitschrift für die gesamte Staatswissenschaft, Vol. 117, pp. 610–634.
4. De Vecchi, Nicolo (1995). Entrepreneurs, Institutions and Economic Change. The Economic Thought of J. A. Schumpeter (1905–1925). Edward Elgar Publishing Company, Brookfield, Vermont, pp. 16–19 and pp. 144–146, and p. 147.
5. Ebner, Alexander (2000). “Schumpeter and the’ schmollerprogram’: Integrating Theory and History in the Analysis of Economic Development.” Evolutionary Economics, Vol. 10, p. 356.