Azhar Aziz, Endang Haryani, and nurmaida irawani siregar. “Education Psychology and Learning Performance: Does Mental Skills and Mental Techniques Influences Learning Performance? A Survey Study on Indonesian Educational Institutions”. Revista De Psicología Del Deporte (Journal of Sport Psychology), vol. 31, no. 1, Mar. 2022, pp. 26-39, https://rpd-online.com/index.php/rpd/article/view/632.