1. Nitrogenous compounds;Bremner,1967
2. Nitrogen-total;Bremner,1982
3. Minerals in soil environments;Dixon;Soil Sci. Soc. Am., Madison, WI,1989
4. Chemical composition and physical properties of humic substances;Flaig,1975
5. Myceloid growth of Arthrobacter globiformis and other Arthrobacter species;Germida;J. Bacteriol.,1980