Hughes, Richard E.,  
Diachronic Variability in Obsidian Procurement Patterns in Northeastern California and Southcentral Oregon. Berkeley et al.: University of California Press, 1969. xxii, 429 pages. Paperback. 4to. 846 g
* University of California Publications in Anthropology, Vol. 17. - Gebrauchsspuren.  
Bestell-Nr.141014 | ISBN: 0-520-09699-1
Hughes | 
Nordamerika	|	
Geologie	|	
Petrographie	|	
Mineralogie	|	
Obsidian	|	
Kristallographie	|	
Archaeologie