Tull D S <br/><br/>
Marketing research: measurement six methods 
Tull D S; Hawkins D I 
 - 6 
 - New Delhi  New Delhi, Prentice-Hall  1993 
 - 927p 
<br/><br/><label>ISBN: </label>81-203-0961-8 
<br/><br/><label>Source: </label>Textbook