1. J. R. Summer and G. F. Somers, “Laboratory Experiments in Biological Chemistry,” Academic Press, New York, 1944.
2. D. Kay, “Techniques for Electron Microscopy,” Blackwell Scientific Publication Co., New York, 1964.
3. R. E. Gordon, W. C. Haynes and C. H. Pang, “The GenusBacillus,” United States Department of Agriculture, Washington, D. C., 1973.
4. P. H. A. Sneath, in “Bergey’s Manual of Systematic Bacteriology,” Vol. 2., ed. by P. H. A. Sneath, N. S. Main, M. E. Sharpe and J. G. Holt, The Williams and Wilkins Company, Baltimore 1986, pp. 1105-1139.