Soil degradation  proceeding of the Land Use Seminar on Soil Degradation, Wageningen, 13-15 October 1980 
edited by D.Bods, D.B.Davies, A.E.Johnston 
 - Rotterdam  A. A. Balkema  1981 
 - 280 p.: ill.  ; 25 cm. 
<br/><br/>Includes bibliographies 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Soil degradation--Congresses<br/>Humus--Congresses<br/>Land use, Rural--Congresses