Nitrogen as an ecological factor. 

 - Oxford :  Blackwell Scientific Publications,  1983. 
 - 464 p. 
<br/><br/><label>ISBN: </label>0632010746 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Nitrogen cycle--Congresses.<br/> Nitrogen--Fixation--Congresses.<br/> Nitrogen--Metabolism--Congresses.<br/> Nitrogen--Physiological effect--Congresses.