Khadka, D.K., et al. “Methotrexate Versus Methotrexate Plus Folic Acid in the Treatment of Moderate to Severe Plaque Psoriasis: A Randomized Clinical-Trial”. Nepal Journal of Dermatology, Venereology & Leprology, vol. 14, no. 1, Sept. 2016, pp. 29-36, doi:10.3126/njdvl.v14i1.15835.