Colwell J. D. <br/><br/>
Computations for studies of soil fertility and fertilizer requirements / 
J.D Colwell 
 - Farnham Royal :  Commonwealth agricultural Bureaux,  1978. 
 - ix, 297p. :  30cm. 
<br/><br/>Includes Bibliographical references. 
<br/><br/><label>ISBN: </label>0851984371 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Soil fertility--Computer programs
<br/><br/><label>LC Class. No.: </label>S633  / .C65 1978