Kotpal, R. L. <br/><br/>
Echinodermata :  a textbook for college & university students / 
R. L. Kotpal 
 - 5th ed. 
 - Meerut :  Rastogi,  1982 
 - 219 p. :  ill. ;  18 cm. 
<br/><br/>Includes bibliographical references : p.213-214 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Echinodermata