STANSFIELD, W. D. (1977). The Science of evolution. Macmillan.
Cita Chicago (17th ed.)STANSFIELD, William D. The Science of Evolution. New York: Macmillan, 1977.
Cita MLA (9th ed.)STANSFIELD, William D. The Science of Evolution. Macmillan, 1977.
Atenció: Aquestes cites poden no estar 100% correctes.