Cita APA (7a ed.)

Cunningham, F. G., & Williams, J. W. (2005). Williams obstetrics (22nd ed.). McGraw-Hill.

Cita Chicago Style (17a ed.)

Cunningham, F. Gary, y J. Whitridge Williams. Williams Obstetrics. 22nd ed. New York ; Madrid: McGraw-Hill, 2005.

Cita MLA (9a ed.)

Cunningham, F. Gary, y J. Whitridge Williams. Williams Obstetrics. 22nd ed. McGraw-Hill, 2005.