00643cam a22002057a 450000500170000000800410001701000100005801100100006803500100007808200160008811000510010424500830015526000390023830000230027749000350030065000110033565000240034665000320037083000350040220220817043109.0971010s1987            r     00010     d  a65560  a66532  a74824  a631.422bS6  aSoil Science Society of America. Madison, Wis. 0aSoil fertility and organic matter as critical components of production systems  aMadison, Wis :bThe Society,c1987  a166 p.b; gráfs. 0aSSSA Special publicationv; 1914aHumus.14aSuelosxFertilidad.14aSuelosxMateria orgánica.0 aSSSA Special publicationv; 19