Nugroho, Indra, Moch Chotim, and Dwijanto Dwijanto. “KEEFEKTIFAN PENDEKATAN PROBLEM BASED LEARNING TERHADAP KEMAMPUAN BERPIKIR KREATIF MATEMATIK”. Unnes Journal of Mathematics Education 2, no. 1 (March 7, 2013). Accessed April 28, 2024. http://journal.unnes.ac.id/sju/ujme/article/view/3319.