ALLEN JOSEPH. (1979). EFFECTIVE BUSINESS COMMUNICATION A PRATICAL GUIDE. GOODYEAR.
Chicago-viite (17. p.)ALLEN JOSEPH. EFFECTIVE BUSINESS COMMUNICATION A PRATICAL GUIDE. CALIFORNIA: GOODYEAR, 1979.
MLA-viite (9. p.)ALLEN JOSEPH. EFFECTIVE BUSINESS COMMUNICATION A PRATICAL GUIDE. GOODYEAR, 1979.
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