The Colorado river region and John Wesley Powell / 
by Mary C. Rabbitt...[et al.]. 
 -- Washington :   United States Government Printing Office,   1969 
 - 145 p. -- 
 (Geological Survey Professional Paper  ; 669).
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geología<br/>Hidrología<br/>Río Colorado
<br/><br/><label>Universal Decimal Class. No.: </label>556.53(282.271.4)