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3. Application of pot ale to land;Naylor;Annuals in Applied Biology,1981
4. Changes in heavy metal/organic extractability and organic matter fractions after vermicomposting of sludges from a paper mill, a wastewater treatment plant and animal waste biproducts;Elvira;Fresenius Environmental Bulletin,1995
5. Long term effects of sewage sludge application on grassland;Aitken;Soil Use and Management,1995