Stern, C. (1949). Children discover arithmetic: An introduction to structural arithmetic. Harper.
Chicago-referens (17:e uppl.)Stern, Catherine. Children Discover Arithmetic: An Introduction to Structural Arithmetic. New York: Harper, 1949.
MLA-referens (9:e uppl.)Stern, Catherine. Children Discover Arithmetic: An Introduction to Structural Arithmetic. Harper, 1949.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.