APA (7th ed.) Citation

Heer, F. (1961). The medieval world: Europe, 1100-1350. New American Library.

Chicago Style (17th ed.) Citation

Heer, Friedrich. The Medieval World: Europe, 1100-1350. New York: New American Library, 1961.

MLA (8th ed.) Citation

Heer, Friedrich. The Medieval World: Europe, 1100-1350. New American Library, 1961.

Warning: These citations may not always be 100% accurate.