Ristida R. EFFORTS TO IMPROVE THE QUALITY OF LEARNING THROUGH TEACHER ACTIVITIES IN DEVELOPING MATERIALS AS ONE OF THE REFERENCES AND LEARNING SOURCES IN SMA NEGERI 2 SIPORA. JIGE [Internet]. 2022 Mar. 16 [cited 2024 Nov. 5];1(1):19-28. Available from: https://ejurnal-unespadang.ac.id/index.php/JIGE/article/view/534