Febrianto, P. T., S. Mas’udah, and L. A. Megasari. “Implementation of Online Learning During the Covid-19 Pandemic on Madura Island, Indonesia”. International Journal of Learning, Teaching and Educational Research, vol. 19, no. 8, Aug. 2020, pp. 233-54, http://ijlter.myres.net/index.php/ijlter/article/view/271.