Rachmad Syarifuddin Hidayatullah, Sudirman Rizki Ariyanto, Muhaji, Husni Mubarok, and Abebayehu Yohannes. 2020. “Collaborative Problem-Based Learning: An Analysis of Problem-Solving Skills in Vocational Schools”. IJORER : International Journal of Recent Educational Research 1 (3). Indonesia, 209-17. https://doi.org/10.46245/ijorer.v1i3.62.