Afriza, D. A., and N. E. A. Nasution. “Comparison of The Learning Outcomes of Junior High School Students Utilizing Audio-Visual and Chart Learning Media to Study Ecosystem”. META: Journal of Science and Technological Education, vol. 1, no. 1, June 2022, pp. 46-57, https://meta.amiin.or.id/index.php/meta/article/view/4.