Petersen, Morris S. <br/><br/>
Interpreting earth history :  a manual in history geology / 
Morris S. Petersen, J. Keith Rigby. 
 - 3rd ed. 
 - Iowa :  Wm C. Brown,  1982. 
 - 211 p. :  ill. ;  28 cm. 
<br/><br/> Open access. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Historical geology.<br/>Historical geology--North America.