siagian roy, Nathanael Sitanggang, M. Joharis Lubis. Project-Based Learning Governance on Natural Materials Improving the Creativity of Class VIII Students of SMP Negeri 1 Sigumpar. EHDJ [Internet]. 2022Sep.30 [cited 2024May5];7(2):77-84. Available from: https://journal2.unusa.ac.id/index.php/EHDJ/article/view/2964