Putra , Made Indrayana, et al. “Solving Yin-Yang Puzzles Using Exhaustive Search and Prune-and-Search Algorithms”. (IJCSAM) International Journal of Computing Science and Applied Mathematics, vol. 8, no. 2, Aug. 2022, pp. 52-65, https://journal.its.ac.id/index.php/ijcsam/article/view/4669.