Knodel, J. E. (1974). The decline of fertility in Germany, 1871-1939: By John E. Knodel. Princeton University Press.
Chicago-referens (17:e uppl.)Knodel, John E. The Decline of Fertility in Germany, 1871-1939: By John E. Knodel. Princeton, New Jersey: Princeton University Press, 1974.
MLA-referens (8:e uppl.)Knodel, John E. The Decline of Fertility in Germany, 1871-1939: By John E. Knodel. Princeton University Press, 1974.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.