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2. Microbial Ecology, Wiley, New York, 1971, chs, 10 and 11.
3. Principles of Microbial Ecology, Prentice-Hall, Englewood Cliffs, N.J., 1960, pp. 120-123.
4. Studies in intermicrobial symbiosis. Saccharomyces cerevisiae and Lactobacillus casei
5. Interactions in a mixed bacterial population growing on methane in continuous culture