Margiyan, Mochamad Egi, Sri Nuraini, and Hernawan. 2022. “The Effect of Referee Knowledge, Leadership Style and Confidence on the Performance of Hockey Referee”. Gladi : Jurnal Ilmu Keolahragaan 13 (02):161-77. https://journal.unj.ac.id/unj/index.php/gjik/article/view/23673.