Calan [package insert]. New York, NY: Pfizer, Inc.;2006 June.
Calan SR [package insert]. New York, NY: Pfizer, Inc.;2003 July.
Covera-HS [package insert]. New York, NY: Pfizer, Inc.;2006 May.
Isoptin SR [package insert]. Charlotte, NC: FSC Laboratories, Inc.;2002 November.
Verelan [package insert]. Milwaukee, WI: Schwarz Pharma;2007 August.
Verelan PM [package insert]. Milwaukee, WI, Schwarz Pharma;2007 May.
Food and Drug Administration, Center for Drug Evaluation and Research. Electronic orange book: Approved drug products with therapeutic equivalence evaluations. FDA Web site. Available at: http://www.fda.gov/cder/ob/. Accessed March 22, 2007.
Briggs GG, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 7th ed. Philadelphia (PA): Lippincott Williams & Wilkins;2005.
National Library of Medicine (US). Drugs and Lactation Database (LactMED). NLM Web site. Available at: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT. Accessed March 22, 2007.