1. Adelson, L. M., A. Schatz, and G. S. Trelawny, 1957. Metabolism of lipids and lipid derivatives by a soil actinomycete. J. Bacteriol. 73:148.
2. Agarwal, G. S., K. S. K. Rao, and L. S. Negi, 1958. Influence of certain species of earthworms on the structure of some hill soils. Curr. Sci. 27:213.
3. Alexander, M., 1961. Introduction to soil microbiology. New York:John Wiley.
4. Aschan, O., 1921. Humoceric acid. Finska Kern, sanfundets Medal. 30:37. Chem. Abstr. 16:1567 (1921).
5. Asinger, F., 1956. Chemie und Technologie der Paraffin—Kohlenwasserstoffe. Berlin:Akademie.