Edwards, C. W. (1963). A test of arithmetic principles, elementary form. University Microfilms.
Cita Chicago (17th ed.)Edwards, Charles Walter. A Test of Arithmetic Principles, Elementary Form. [Ann Arbor, Mich: University Microfilms, 1963.
Cita MLA (9th ed.)Edwards, Charles Walter. A Test of Arithmetic Principles, Elementary Form. University Microfilms, 1963.
Atenció: Aquestes cites poden no estar 100% correctes.