Tuğba Aydoğdu İskenderoğlu, İsmail Erkan, Ayşegül Serbest. “Classification of SBS Mathematics Questions Between 2008-2013 Years With Respect to PISA Competency Levels”. Turkish Journal of Computer and Mathematics Education (TURCOMAT) 4, no. 2 (November 26, 2013): 147–168. Accessed May 3, 2024. https://turcomat.org/index.php/turkbilmat/article/view/55.