Merriam-Webster's guide to business correspondence : a merriam-webster
Merriam-Webster's, Incorporated, 1993
 Buku Referensi
Munter, Mary
Guide to managerial communication: effective business writing and speaking
Prentice-Hall, 1982
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Ewald, Helen Rothschild
Business communication
Prentice-Hall International, 1997
 Buku Teks
Locker, Kitty O.
Business and administrative communication
Irwin, 1995
 Buku Referensi
Locker, Kitty O.
Business and administrative communication
McGraw-Hill/Irwin, 2000
 Buku Teks