Ritartini. “Improving Collaborative Ability and Learning Achievement in Mathematics Through the Project-Based Learning (PjBL) Model Using Diagram Image Media for Class VI Students of SD Negeri Purwoharjo Academic Year 2021/2022”. IJCER (International Journal of Chemistry Education Research), vol. 7, no. 2, Oct. 2023, pp. 76-80, doi:10.20885/ijcer.vol7.iss2.art6.