1. Surface Chemistry;Bikerman,1958
2. A potentiometric study of the humic acids derived from coal;Brown;Fuel Sci. Pract.,1938
3. Physical Properties of Coal Influencing the Beneficiation of Fine Coal;Burdon,1960
4. Microaggregates in soils;Edwards;J. Soil Sci.,1967
5. Coagulation of humic substances;Edzwald,1978