R. Sathiyasundar and K. Valliappan, “AN IMPROVED RP-HPLC METHOD FOR THE SIMULTANEOUS ESTIMATION OF ASPIRIN, ATORVASTATIN, AND CLOPIDOGREL IN PHARMACEUTICAL FORMULATION USING EXPERIMENTAL DESIGN METHODOLOGY”, Int J Pharm Pharm Sci, vol. 6, no. 11, pp. 279–283, Nov. 2014.