The sea monsters /  Rick Riordan. 

 - New York :   Hyperion Books,  c2006.  
 - 270p. 
 -  Percy jackson and the olympians, bk.2   .
<br/><br/><label>ISBN: </label>9781423103349   
<br/><br/><label>Dewey Class. No.: </label>FIC R585se 2006