APA (7th ed.) Citation

Greenhill, J. P., & Friedman, E. A. (1974). Biological principles and modern practice of obstetrics. Saunders.

Chicago Style (17th ed.) Citation

Greenhill, Jacob P., and Emanuel A. Friedman. Biological Principles and Modern Practice of Obstetrics. Philadelphia [u.a.]: Saunders, 1974.

MLA (9th ed.) Citation

Greenhill, Jacob P., and Emanuel A. Friedman. Biological Principles and Modern Practice of Obstetrics. Saunders, 1974.