Ray, Michael L. <br/><br/>
Unobtrusive marketing research techniques / 
Michael L. Ray, Peter N. Sherrill. 
 - Stanford:   Stanford University,   1972.  
 - 13 p. ;  28 cm. 
 -  81 .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Marketing research
<br/><br/><label>Dewey Class. No.: </label>658.83