Cresci, M. W. (1992). Complete book of model business letters. HCM.: ĐHTH.
Dyfyniad Arddull ChicagoCresci, Martha W. Complete Book of Model Business Letters. HCM.: ĐHTH, 1992.
Dyfyniad MLACresci, Martha W. Complete Book of Model Business Letters. HCM.: ĐHTH, 1992.
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