Chapman , Stephen R. <br/><br/>
Crop production :  principles and practices / 
Stephen R. Chapman and Lark P. Carter 
 - San Francisco :  W. H. Freeman,  1976 
 - 566 p. :  ill. ;  24 cm. 
<br/><br/>Includes bibliographies and index 
<br/><br/><label>ISBN: </label>0716705818 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Field crops<br/>Field crops--North America