Ullman, Jeffrey D. <br/><br/>
Principles of database systems.- 2nd ed. 
Jeffrey D Ullman 
 - 2nd ed. 
 - Delhi:  Galgotia publications;  1991. 
 - vii, 484p. 
<br/><br/><label>Subjects--Index Terms: </label>Database systems. 
<br/><br/><label>Universal Decimal Class. No.: </label>681.3.02  / ULL