MLA

Ritchie, Christine S, et al. Handbook of Clinical Nutrition and Aging. Humana Press, 2009.

APA

Ritchie, C. S, Bales, C. W, Christine S. Ritchie, C. S. Ritchie, & Ritchie, C. Seel. (2009). Handbook of Clinical Nutrition and Aging. Humana Press.

Chicago

Ritchie, Christine S., Connie W Bales, Christine S. Ritchie, and Christine Seel Ritchie. Handbook of Clinical Nutrition and Aging. : Humana Press, 2009.