Widyaningsih, Erma. “Application Of The Group Investigation Model, Using Whatsapp To Increase Learning Outcomes For Class VI Students Of Sd Negeri Trayu Samigaluh Academic Year 2020/2021”. IJCER (International Journal of Chemistry Education Research) 6, no. 2 (October 10, 2022): 102–107. Accessed May 8, 2024. https://journal.uii.ac.id/IJCER/article/view/22682.