Cita APA

Gaylard Simpson, G., & Beck, W. (1969). Life an introduction to biology. New York (EUA):.

Citación estilo Chicago

Gaylard Simpson, G., y W.S Beck. Life an Introduction to Biology. New York (EUA):, 1969.

Cita MLA

Gaylard Simpson, G., y W.S Beck. Life an Introduction to Biology. New York (EUA):, 1969.