Cita APA (7a ed.)

Hay, R., & Walker, A. J. (1989). An introduction to the physiology of crop yield. Longman Scientific & Technical.

Cita Chicago Style (17a ed.)

Hay, R.K.M, y Andrew J. Walker. An Introduction to the Physiology of Crop Yield. Harlow: Longman Scientific & Technical, 1989.

Cita MLA (9a ed.)

Hay, R.K.M, y Andrew J. Walker. An Introduction to the Physiology of Crop Yield. Longman Scientific & Technical, 1989.