APA-referens (7:e uppl.)

Heer, F. (1962). The medieval world: Europe. New American Library.

Chicago-referens (17:e uppl.)

Heer, Friedrich. The Medieval World: Europe. New York: New American Library, 1962.

MLA-referens (9:e uppl.)

Heer, Friedrich. The Medieval World: Europe. New American Library, 1962.