R. J, S. L.M, R. M.A, H. A, and M. Marufuzzaman, “Probable Maximum Precipitation Comparison using Hershfield’s Statistical Method and Hydro-Meteorological Method for Sungai Perak Hydroelectric Scheme”, IJET, vol. 7, no. 4.35, pp. 603–608, Nov. 2018, doi: 10.14419/ijet.v7i4.35.22922.