http://repository.uhamka.ac.id/id/eprint/12709/
Enhancing Conceptual Knowledge about Shape through Realistic Mathematics Education
Pramudiani, Puri
http://repository.uhamka.ac.id/id/eprint/12709/1/03_A_2017_Article_JIPD_Puri%20dkk_Conceptual%20Shape.pdf