Calleo, D. P. (1980). The German problem reconsidered: Germany and the world order, 1870 to the present. Cambridge University Press.
Chicago-referens (17:e uppl.)Calleo, David P. The German Problem Reconsidered: Germany and the World Order, 1870 to the Present. Cambridge: Cambridge University Press, 1980.
MLA-referens (9:e uppl.)Calleo, David P. The German Problem Reconsidered: Germany and the World Order, 1870 to the Present. Cambridge University Press, 1980.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.