Pearson, Robert Carl,  1926- <br/><br/>
Cambrian(?), Middle Proterozoic, and Archean rocks penetrated in a borehole near Argenta, Beaverhead County, Montana, and some paleogeographic and structural implications / 
by Robert C. Pearson. 
 - Washington, D.C. :  U.S. Government Printing Office.,  1996. 
 - iii, 15 p. :  ill., maps ;  28 cm. 
 - Belt supergroup in the Highland Mountains and probable equivalent rocks in the Pioneer and Anaconda ranges, southwestern Montana ;  B U.S. Geological Survey bulletin ;  2121 .
<br/><br/>Includes bibliographical references (p. 14-15). 
<br/><br/><label>LC Class. No.: </label>QE75  QE627.5.M9  / .B9 no. 2121-B