P. S. M. A. Sembiring, F. Elina Gultom, and M. Debora, “Penerapan Optimalisasi Keterampilan 4c (Creative Thinking, Critical Thinking And Problem Solving, Communication, Collaboration) Dalam Pembelajaran Contextual Oral Language Skills”, JIK, vol. 7, no. 3, pp. 391–399, Dec. 2023.