1. Cerny, G. (1976). Method for the distinction of Gram-negative from Gram-positive bacteria. Eur. J. Appl. Microbiol. 3, 223?225
2. Cowan, S. T. (1974). Cowan and Steel's Manual for the Identification of Medical Bacteria. 2nd ed. Cambridge: University Press
3. Cruickshank, R., Duguid, J.P., Marmion, B.P., Swain, R.H.A. (1973). Medical Microbiology. 12th ed. Vol. 1, p. 29. Churchill Livingstone
4. Davis, B.D., Dulbecco, R., Eisen, H., Ginsberg, H.S., Wood, W.B. (1967). Microbiology. p. 31. Harper International
5. Henriksen, S.D. (1976). Moraxella, Neisseria, Branhamella and Acinetobacter. Annu. Rev. Microbiol. 30, 63?83