Sari, D., M. Mulyono, and T. Sri Noor Asih. “Mathematical Problem Solving Ability Viewed from Extrovert Introvert Personality Types on Cooperative Learning Models Type Rally Coach”. Unnes Journal of Mathematics Education Research, Vol. 8, no. 2, Jan. 2019, pp. 141-6, https://journal.unnes.ac.id/sju/ujmer/article/view/28019.