Arnott, Michael. <br/><br/>
The biogas/biofertilizer business handbook. 

 - 3rd. ed. 
 - Batangas City :  Philippine Center for Appropriate Technology and Training,  1985. 
 - xvi , 186 p. :  illus. ;  27 cm. 
<br/><br/> Includes appendices. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Biofertilizers.<br/>Nitrogen -- Fixation.