Pratama, Christianus Yanuarli Agung, and Yustinus Sukarmin. “The Relationship of Teacher Certification, Work Motivation, and the Working Period With the Performance of Physical Education Teachers of Elementary Schools”. Journal of Education, Health and Sport 9, no. 4 (April 2, 2019): 110–123. Accessed November 24, 2024. https://apcz.umk.pl/JEHS/article/view/6767.