Guffey, Mary Ellen. Essentials of business communication / Mary Ellen Guffey. - 6th ed. - Mason, Ohio : Thomson/South-Western, c2004 - xxxii, 511 p. : ill. (some col.) ; 28 cm. ISBN: 0324233647 Subjects--Topical Terms: Business communication.Business writing.English language --Business English. Subjects--Index Terms: Giao tiếp Kỹ năng viết Tiếng Anh thương mại Dewey Class. No.: 808/.06665