Cita APA (7a ed.)

Heer, F., & Sondheimer, J. (1962). The medieval world: Europe 1100-1350. New American Library.

Cita Chicago Style (17a ed.)

Heer, Friedrich, y Janet Sondheimer. The Medieval World: Europe 1100-1350. New York: New American Library, 1962.

Cita MLA (9a ed.)

Heer, Friedrich, y Janet Sondheimer. The Medieval World: Europe 1100-1350. New American Library, 1962.