Hallenberg, Heather. <br/><br/>
The lake of the avernus and its elusive mystery. 

 - Missouri-US :   University of Missouri-Columbia,   1978. 
 - páginas 49-59 :   ilustraciones blanco y negro 
 - Anual 
 - No.12 (1978) 
 - MUSE. Annual of the Museum of art and archaeology ;   no.12 .
 - University of Missouri-Columbia. .