SAS language and procedures :  usage 2, version 6. 

 - 1st ed. 
 - Cary, NC :  SAS Institute,  c1991. 
 - xxvi, 649 p. :  ill. ;  28 cm. 
<br/><br/><label>ISBN: </label>1555444458 
<br/><br/><label>Dewey Class. No.: </label>519 SAS 1991 A028 Or.