Cita APA (7a ed.)

Gies, J., & Gies, F. (1979). Life in a medieval Castle. Harper & Row.

Cita Chicago Style (17a ed.)

Gies, Joseph, y Frances Gies. Life in a Medieval Castle. New York, [etc.]: Harper & Row, 1979.

Cita MLA (9a ed.)

Gies, Joseph, y Frances Gies. Life in a Medieval Castle. Harper & Row, 1979.