Mallory, V. S., Polishook, W. M., Chapman, I. E., & Starkey, S. H., Jr. (1956). Key to Commercial arithmetic: Second edition. Benj. H. Sanborn.
Lua i Stíl Chicago (17ú heag.)Mallory, Virgil Sampson, William M. Polishook, Ivan E. Chapman, agus S. Herbert Starkey, Jr. Key to Commercial Arithmetic: Second Edition. Syracuse, N.Y.: Benj. H. Sanborn, 1956.
Lua MLA (8ú heag.)Mallory, Virgil Sampson, et al. Key to Commercial Arithmetic: Second Edition. Benj. H. Sanborn, 1956.
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