F. U. Abidin, M. H. Sarfraz, H. Javaid, A. Khan, S. Khan, and H. Javaid, “Therapeutic Efficacy of Topical Olopatadine 0.1% Versus Ketotifen Fumarate in Allergic Conjunctivitis”, PAFMJ, vol. 72, no. 1, pp. 16–19, Feb. 2022.