1. Alexander, M., Introduction to Soil Microbiology. John Wiley and Sons, Inc., New York (1961).
2. Breed, R. S., Murray, E. G. D. and Smith, N. R., Bergey's Manual of Determinative Bacteriology. 7th ed. Williams & Wilkins Co., Baltimore (1957).
3. Cochrane, V. W., Physiology of Fungi. John Wiley and Sons, Inc., N.Y. (1958).
4. Cooke, W. B., Ecology37 857?858 (1958).
5. Doak, D. D., Am. Midland Naturalist54 443?451 (1955).