Shurter, R. L., & Nichols, F. G. (1948). Effective letters in business. McGraw-Hill Book Co.
Chicago-viite (17. p.)Shurter, Robert L., ja Frederick George Nichols. Effective Letters in Business. New York: McGraw-Hill Book Co, 1948.
MLA-viite (8. p.)Shurter, Robert L., ja Frederick George Nichols. Effective Letters in Business. McGraw-Hill Book Co, 1948.
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