National Council of Teachers of Mathematics. (1954). The Arithmetic teacher. National Council of Teachers of Mathematics.
Chicago-referens (17:e uppl.)National Council of Teachers of Mathematics. The Arithmetic Teacher. Washington, D.C: National Council of Teachers of Mathematics, 1954.
MLA-referens (9:e uppl.)National Council of Teachers of Mathematics. The Arithmetic Teacher. National Council of Teachers of Mathematics, 1954.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.