R. C. Welerubun, H. L. Wambrauw, J. Jeni, D. Wolo, and I. Damopolii, “CONTEXTUAL TEACHING AND LEARNING IN LEARNING ENVIRONMENTAL POLLUTION: THE EFFECT ON STUDENT LEARNING OUTCOMES”, Pri.Mag.:J.I.K., vol. 3, no. 1, pp. 106-115, Jan. 2022.