Tompkins, Peter. <br/><br/>
Secrets of the soil / 
Peter Tompkins & Christopher Bird. 
 - London :  Viking Arkana,  c1991. 
 - xxiv, 444 p. :  ill. 
<br/><br/><label>ISBN: </label>0670835617  
<br/><br/><label>LCCN: </label>91065068     
<br/><br/><label>Subjects--Topical Terms: </label><br/>Soils.<br/>Soil management.<br/>Organic farming.<br/>Agricultural ecology.