Hariyanto, Hariyanto, Soetarno Joyoatmojo, Joko Nurkamto, and Gunarhadi Gunarhadi. 2019. “Developing Inquiry-Based Learning Materials to Promote Students’ Academic Achievement”. International Journal of Learning, Teaching and Educational Research 18 (1):50-61. https://ijlter.net/index.php/ijlter/article/view/604.