1. B. Finnerty, in: Microbial Energy Conversion, p. 83. Ed. H. G. Schlegel and J. Barnea. Erich Golze KG, Göttingen 1976.
2. B. Berg, Archs Microbiol.118, 61 (1978).
3. L. A. Spano, in: Microbial Energy Conversion p. 157. Ed. H. G. Schlegel and J. Barnea. Erich Goltze KG, Göttingen 1976.
4. H. Sahm, in: Rothenburger Symposium, p. 75. Braun AG, Melsungen 1978.
5. The National Biomass Program, 3rd Annual Biomass Energy System Conference Proceedings, SERI/TP 33-285 (1979).