Cita APA (7th ed.)

Williams, J. W., Cunningham, F. G., MacDonald, P. C., & Gant, N. F. (1989). Williams obstetrics (18th ed.). Appleton & Lange.

Cita Chicago (17th ed.)

Williams, J. Whitridge, F. Gary Cunningham, Paul C. MacDonald, i Norman F. Gant. Williams Obstetrics. 18th ed. Norwalk, Conn: Appleton & Lange, 1989.

Cita MLA (9th ed.)

Williams, J. Whitridge, et al. Williams Obstetrics. 18th ed. Appleton & Lange, 1989.