Cita APA (7a ed.)

Pyke, D., & Medawar, J. S. (1971). Family planning. Penguin Books.

Cita Chicago Style (17a ed.)

Pyke, David, y J. S. Medawar. Family Planning. Harmondsworth: Penguin Books, 1971.

Cita MLA (9a ed.)

Pyke, David, y J. S. Medawar. Family Planning. Penguin Books, 1971.