Gehrig, John Leonard. <br/><br/>
Middle Pennsylvanian brachiopods from the Mud Springs Mountains and Derry Hills, New Mexico. 

 - Socorro,  State Bureau of Mines and Mineral Resources, New Mexico Institute of Mining and Technology,  1958. 
 - 24 p.  6 plates, maps.  28 cm. 
<br/><br/>Bibliography: p.22. 
<br/><br/><label>LCCN: </label>gs 59000185  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Brachiopoda, Fossil.<br/>Paleontology--Pennsylvanian.<br/>Paleontology--New Mexico--Sierra County.
<br/><br/><label>LC Class. No.: </label>QE796  / .G4 
<br/><br/><label>Dewey Class. No.: </label>564.80978967