Riordan, Rick. <br/><br/>
The House of Hades:  Book #4- The Heroes of Olympus / 
Rick Riordan. 
 - First edition. 
 - 597 pages ;  22 cm. 
 - The Heroes of Olympus .
 - Heroes of Olympus ;  book four .
<br/><br/> Greek and Roman demigods from the Prophecy of Seven must work together to seal the Doors of Death, and help Percy and Annabeth escape the Underworld in the process. 
<br/><br/><label>ISBN: </label>9781423146728 :  $19.99 1423146727 :  $19.99 
<br/><br/><label>LCCN: </label>2013015946 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Roman mythology--Fiction.<br/>Greek mythology--Fiction.<br/>Giants--Fiction.<br/>Camps--Fiction.<br/>Hera (Greek deity)--Fiction.<br/>Gaia (Greek deity)--Fiction.
<br/><br/><label>LC Class. No.: </label>PZ7.R4829  / Hou 2013 
<br/><br/><label>Dewey Class. No.: </label>[Fic]