GUFRON, E.; SANTOSA, A.; KADARMANTO, A. PENINGKATAN IMPLEMENTASI MODEL PROBLEM BASED LEARNING UNTUK MENINGKATKAN HIGHER ORDER THINKING SKILLS (HOTS) SISWA DI BONDOWOSO (Studi Kasus MAS Miftahul Ulum Pancoran). SIGMA : JURNAL PENDIDIKAN MATEMATIKA DAN SAINS, [S. l.], v. 3, n. 1, p. 26–35, 2025. Disponível em: https://journal.unibo.ac.id/index.php/sigma/article/view/1076. Acesso em: 15 feb. 2026.