Setianti N. Instructional Packages Geography Based on Ecosystem (PIGeoEk) Development in Improving Students’ Knowledge About Ecosystem Concepts and Relation to Students’ Environmental Behavior. IJEEM [Internet]. 2018Jan.21 [cited 2025Jul.4];3(1):1 - 22. Available from: http://103.8.12.212:33180/unj/index.php/ijeem/article/view/5621