APA

Frost H., Saunders-Smith G., . (2001). The Digestive System. Minnesota: Capstone Press.

Chicago

Frost Helen, Saunders-Smith Gail, . 2001. The Digestive System. Minnesota: Capstone Press.

Harvard

Frost H., Saunders-Smith G., . (2001). The Digestive System. Minnesota: Capstone Press.

MLA

Frost Helen, Saunders-Smith Gail, . The Digestive System. Minnesota: Capstone Press. 2001.