Willey, Gordon <br/><br/>
The ruins of Altar de Sacrificios, departments of Peten, Guatemala :  An introduction 

 - Cambridge :  Harvard university-<The> Peabody museum of american archaeology and ethnology,  1969 
 - 49 p: :  ill., cartes h. t., tab. 
 - Papers of the Peabody museum of american archaeology and ethnology, 62(1) .
<br/><br/>bibliogr. p. 48-49