MEDINA, J. R.; GARCIA, C. A.; HURTADO, M.; DOMINGUEZ-RAMIREZ, A. M. SIMULTANEOUS DETERMINATION OF KETOPROFEN AND ACETAMINOPHEN IN FIXED-DOSE COMBINATION FORMULATIONS BY FIRST-ORDER DERIVATIVE SPECTROSCOPY: APPLICATION TO DISSOLUTION STUDIES. International Journal of Pharmacy and Pharmaceutical Sciences, v. 8, n. 2, p. 244-248, 1 Feb. 2016.