Statistics of crop responses to fertilizers․ 

 - Rome ;  London :  F.A.O. ։  H.M.S.O.,  1966. 
 - viii, 112 p. :  illus. (forms), tables, diagrs. ;  24 cm. 
 - Food and agriculture organization of the United Nations .
<br/><br/>Bibliography: p. [66] 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Fertilizers--Mathematical models.<br/>Fertilizers--Economic aspects.<br/>Crop yields