Sari, E. A., K. Hadiprasetyo, and A. A. Wulandari. “Learning Difficulties of Mathematic Students on Real Analysis Courses With an Online System”. Jurnal Math Educator Nusantara: Wahana Publikasi Karya Tulis Ilmiah Di Bidang Pendidikan Matematika, Vol. 7, no. 1, May 2021, pp. 1-11, doi:10.29407/jmen.v7i1.14766.