APA Citatie

Etkin, W., & Gilbert, L. I. (1968). Metamorphosis: A problem in developmental biology. Appleton-Century-Crofts.

Chicago Style citaat

Etkin, William, en Lawrence I. Gilbert. Metamorphosis: A Problem in Developmental Biology. New York: Appleton-Century-Crofts, 1968.

MLA citatie

Etkin, William, en Lawrence I. Gilbert. Metamorphosis: A Problem in Developmental Biology. Appleton-Century-Crofts, 1968.