The effect of teacher professional certification and work motivation on the performance of elementary school teachers in the Kempas district, Indragiri Hilir regency. JPFKIP [Internet]. 2024 Aug. 10 [cited 2025 May 12];13(4):153-8. Available from: https://primary.ejournal.unri.ac.id/index.php/JPFKIP/article/view/31