R. M. N. Y. Sarpong-Streetor, R. A. Sokkalingam, M. bin Othman, D. L. C. Ching, and H. bin Sakidin, “A Hybrid Autoregressive Integrated Moving Average-phGMDH Model to Forecast Crude Oil Price”, IJEEP, vol. 9, no. 5, pp. 135–141, Jul. 2019.