Frison, George C.. <br/><br/>
Progress & Challenges :   Intriguing Questions Linger after 75 years of Answers. 

 - Oregon-XXU :   The Leach Publishing Group,   2000. 
 - p. 40-42 :   il. 
 - Bimestral 
 - Vol. 2, no. 1, (Jan./Feb. 2000) 
 - Discovering Archaeology ;   no. 1 .
 - Estados Unidos.   The Leach Publishing Group. .
<br/><br/> First Americans. The Archaelogy. 
<br/><br/><br/>Art¡culo en inglés.