PURNAMA, P. W.; RETNOWATI, E. The effectiveness of goal-free problems for studying triangle similarity in collaborative groups. JRAMathEdu (Journal of Research and Advances in Mathematics Education), [S. l.], v. 6, n. 1, p. 32–45, 2020. DOI: 10.23917/jramathedu.v6i1.11198. Disponível em: https://journals2.ums.ac.id/jramathedu/article/view/9338. Acesso em: 17 nov. 2025.