APA (7th ed.) Citation

Purtilo, D. T., & Purtilo, R. B. (1989). A survey of human diseases (2nd ed.). Little Brown.

Chicago Style (17th ed.) Citation

Purtilo, David T., and Ruth B. Purtilo. A Survey of Human Diseases. 2nd ed. Boston: Little Brown, 1989.

MLA (9th ed.) Citation

Purtilo, David T., and Ruth B. Purtilo. A Survey of Human Diseases. 2nd ed. Little Brown, 1989.