Impact :  a Guide to business communication / 
Northey , Margot ; Joan McKibbin . 
 - 5th ed 
 - Toronto:  Prentice Hall ,  2002. 
 - v,328 p,: 
<br/><br/><label>ISBN: </label>0130325481 
<br/><br/><label>LC Class. No.: </label>HF5718  / .N67  2002