Noordyan, M., D. Sofyan, I. Maryati, T. Sritresna, D. Mardiani, B. Basuki, and C. Nurulhaq. “Education in the 21st Century HOTS (Higher Order Thinking Skills) in Mathematical Literacy”. Journal Pekemas, Vol. 3, no. 1, Mar. 2020, pp. 13-17, https://ejournals.institutpendidikan.ac.id/index.php/PEKEMAS/article/view/27.