MLA

O'Neil, Maryadele J. The Merck Index : an Encyclopedia of Chemicals, Drugs, and Biologicals. 13th ed. Whitehouse Station (N.J.): Merck, 2001.

APA

O'Neil, M. J. (2001). The Merck index : an encyclopedia of chemicals, drugs, and biologicals. 13th ed. Whitehouse Station (N.J.): Merck.

Chicago

O'Neil, Maryadele J., The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th ed. Whitehouse Station (N.J.): Merck, 2001.