1. Dirac, P. A. M. Principles of quantum mechanics, 3rd Ed., Oxford: At the Clarendon Press 1958
2. Todd, A.: Wesleyan Symposium on Chemistry (Middlefield, Conn.: Wesleyan University, May 1982
3. Bartlett, N.: Chemistry of the Noble Gases, Holland: Elsevier, 1971
4. See e.g. Adams, R. D., Seleque, J. P.: in Comprehensive organometallic chemistry, Abel, E. W., Wilkinson, G., Stone, F. G., Eds., London: Pergamon Press, 1983
5. See e.g. Cotton, F. A., Wilkinson, G.,: Adv. Inorganic Chemistry, 4th Ed., New York; J. Wiley 1980;