G. Indira Priyadarshini, N. Naga Udayasri, M. Lakshmi Sowmya, and Nagaraju Pappula, “Stability indicating RP-HPLC method development and validation for the simultaneous determination of vilanterol trifinatate and umeclidinium bromide in bulk and pharmaceutical dosage forms ”, World J Pharm Sci, vol. 9, no. 2, pp. 137–143, Jan. 2021.