Gupta , S.P. <br/><br/>
Statistical Methods 

 - New Delhi  Sultan Chand & Sons  2005 
 - 1.1-14.12p. 
<br/><br/><label>ISBN: </label>81-8054-288-2 
<br/><br/><label>Dewey Class. No.: </label>519.5   GUP.P5