William Etkin, R. M. D. A biology of human concern. J.P. Lippincott.
Chicago Style (17th ed.) CitationWilliam Etkin, Robert M. Devlin. A Biology of Human Concern. J.P. Lippincott.
MLA引文William Etkin, Robert M. Devlin. A Biology of Human Concern. J.P. Lippincott.
警告：這些引文格式不一定是100％准確.