Buckingham, B. R. (1953). Elementary arithmetic, its meaning and practice. Ginn.
Cita Chicago (17th ed.)Buckingham, Burdette Ross. Elementary Arithmetic, Its Meaning and Practice. Boston: Ginn, 1953.
Cita MLA (9th ed.)Buckingham, Burdette Ross. Elementary Arithmetic, Its Meaning and Practice. Ginn, 1953.
Atenció: Aquestes cites poden no estar 100% correctes.