Não informado. (1970). Journal for Research in Mathematics Education. National Council of Teachers of Mathematics.
Chicago-referens (17:e uppl.)Não informado. Journal for Research in Mathematics Education. Reston, Va: National Council of Teachers of Mathematics, 1970.
MLA-referens (8:e uppl.)Não informado. Journal for Research in Mathematics Education. National Council of Teachers of Mathematics, 1970.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.