Wahyu, Riska, et al. “Development of Problem-Based Mathematical Learning Tools to Improve Critical Thinking Skills of Grade V Elementary School Students”. Jurnal Teknologi Pendidikan : Jurnal Penelitian Dan Pengembangan Pembelajaran, vol. 8, no. 3, July 2023, pp. 707-13, doi:10.33394/jtp.v8i3.8625.