Ninomiya, TomokoKawasaki, TetsushiMori, SonokoHashimoto, Yoshihiro2018-02-192018-02-192017http://hdl.handle.net/2003/3658710.17877/DE290R-18588enGesellschaft für Didaktik der Mathematik510A Comparative Research of Three Countries on Various Backgrounds of Students and Mathematics Education Through Surveys in Germany, Brazil and Japanconference contribution