Thirkettle, G. L. <br/><br/>
Wheldon's business stastics and statistical method. 

 - 9th. 
 - London :  Pitman,  1981. 
 - 278p. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>0273026968 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Commercial statistics.