Cita APA (7a ed.)

Ryan, M., Abeyratne, F., & Farrington, J. (1981). Animal draught: The economics of revival. Agrarian Research and Training Institute.

Cita Chicago Style (17a ed.)

Ryan, M., Fredrick Abeyratne, y Joseph Farrington. Animal Draught: The Economics of Revival. Colombo, Sri Lanka: Agrarian Research and Training Institute, 1981.

Cita MLA (8a ed.)

Ryan, M., et al. Animal Draught: The Economics of Revival. Agrarian Research and Training Institute, 1981.