Packard, S. S., & Horton, B. (1887). The new Packard commercial arithmetic. S.S. Packard.
Dyfyniad Arddull ChicagoPackard, S. S., and Byron Horton. The New Packard Commercial Arithmetic. New York: S.S. Packard, 1887.
Dyfyniad MLAPackard, S. S., and Byron Horton. The New Packard Commercial Arithmetic. S.S. Packard, 1887.
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