Pardede, Lastiar, Binari Manurung, and Melva Silitonga. “Ecoliteracy Study About Lake Toba On High School Students”. Journal of Learning Improvement and Lesson Study 4, no. 1 (July 1, 2024): 44-50. Accessed September 19, 2024. http://jlils.ppj.unp.ac.id/index.php/jlils/article/view/89.