Sari, C. K., E. Dwiyani, I. U. Machromah, M. Toyib, and D. N. V. Sari. “Enhancing Students’ Critical Thinking by Integrating Contextual Problems Worksheets on Problem Based Learning”. Journal of Education Action Research, vol. 6, no. 1, Feb. 2022, pp. 109-15, doi:10.23887/jear.v6i1.43392.