Riordan, Rick <br/><br/>
House of Hades, The - Book 4. 

 - New York, NY :  Disney - Hyperion Books,  2013. 
 - 583 
 - Heroes of Olympus .
<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. 
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<br/><br/><label>ISBN: </label>9781423146728 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mythology, Roman - Fiction<br/>Mythology, Greek - Fiction