Meylinda, D., E. Simamora, and M. Mukhtar. “Differences in Improving Students’ Communication Ability and Learning Independence Through Problem Based Learning Models and Guided Discovery”. Jurnal Cendekia : Jurnal Pendidikan Matematika, Vol. 5, no. 1, Feb. 2021, pp. 97-13, doi:10.31004/cendekia.v5i1.463.