Gunur, Bedilius, et al. “PENGARUH PENDEKATAN PROBLEM BASED LEARNING BERBANTUAN MASALAH OPEN-ENDED TERHADAP KEMAMPUAN BERPIKIR KRITIS DITINJAU DARI SIKAP MATEMATIS SISWA [THE INFLUENCE OF THE PROBLEM-BASED LEARNING MODEL ASSISTED BY OPEN-ENDED PROBLEMS TOWARDS MATHEMATICAL CRITICAL THINKING SKILLS BASED ON STUDENTS’ MATHEMATICAL ATTITUDE]”. JOHME: Journal of Holistic Mathematics Education, vol. 3, no. 1, Dec. 2019, pp. 1-15, doi:10.19166/johme.v3i1.1912.