Cita APA (7a ed.)

Gray, P. (1961). The encyclopedia of the biological sciences. Reinhold.

Cita Chicago Style (17a ed.)

Gray, Peter. The Encyclopedia of the Biological Sciences. New York [etc.]: Reinhold, 1961.

Cita MLA (9a ed.)

Gray, Peter. The Encyclopedia of the Biological Sciences. Reinhold, 1961.