Twenhofel, William H.  1875-1957. <br/><br/>
Principles of invertebrate paleontology 
[by] Robert R. Shrock [and] William H. Twenhofel. 
 - 2d ed. 
 - New York,  McGraw-Hill,  1953. 
 - 816 p.  illus.  24 cm. 
 - McGraw-Hill series in geology .
<br/><br/> "A revised and enlarged edition of Twenhofel and Shrock, Invertebrate paleontology." 
<br/><br/><label>LCCN: </label>52005341  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Invertebrates, Fossil.<br/>Fósseis
<br/><br/><label>LC Class. No.: </label>QE770  / .T8 1953 
<br/><br/><label>Dewey Class. No.: </label>562