Purba, Ira Devi Anna, et al. “Application of Problem-Based Learning to Enhance Mathematical Reasoning Skills of Phase E Students in Class X-3 SMAN 6 Pekanbaru”. Journal of Educational Sciences, vol. 9, no. 1, Jan. 2025, pp. 58-67, https://doi.org/10.31258/jes.9.1.p.58-67.