APA Style

al, F, G, C, P, C, M, N, F, G, E. (). Williams obstetric, 20th ed . : s.l: Prentice-Hall Int\'l., 1997.

MLA Style

al, F, Gary, Cunningham,, Paul, C, MacDonald,, Norman, F, Gant,, Et. "Williams obstetric, 20th ed". : s.l: Prentice-Hall Int\'l., 1997, . BOOKS.