Opana. Endo Pharmaceuticals. Accessed December 26, 2014 from http://www.endo.com/File%20Library/Products/Prescribing%20Information/OPANA_Injection__prescribing_information.html
Oxymorphone. Micromedex 2.0. Truven Health Analytics. Accessed December 26, 2014 from http://www.micromedexsolutions.com/micromedex2/librarian/