Nitrogen in Indian agriculture (1961-70):   A bibliography of N, NP, NK, NPK and other related factors 
/ European Nitrogen Service Programme 
 - New Delhi:   European Nitrogen Service Programme,   1972 
 - xix, 466p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Bibliography
<br/><br/><label>Subjects--Index Terms: </label>Nitrogen 
<br/><br/><label>Universal Decimal Class. No.: </label>R 016:631.84/(540)  / L2