Robinson, J. B. D. <br/><br/>
The soil nitrogen index and its calibration with crop performance to improve fertilizer efficiency on Arable soil / 
J.B.D. Robinson. 
 - Slough, England :  Commonwealth Agricultural Bureaux,  1975. 
 - 53 p. 
 - Commonwealth Bureau of Soils. Special Publications; no. 1 .
<br/><br/><label>ISBN: </label>0851983405 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Nitrogen fertilizers.<br/>Fertilizers.<br/>Soil fertility.