Cita APA (7a ed.)
Spitzer, H. F. Enrichment of Arithmetic (1a.ed.). Webster Divsion McGraw - Hill.
Cita Chicago Style (17a ed.)
Spitzer, Herbert F. Enrichment of Arithmetic. 1a.ed. Buenos Aires: Webster Divsion McGraw - Hill.
Cita MLA (9a ed.)
Spitzer, Herbert F. Enrichment of Arithmetic. 1a.ed. Webster Divsion McGraw - Hill.
Precaución: Estas citas no son 100% exactas.