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2. Bellman, R., “Some Vistas of Modern Mathematics”, Univ. of Kentucky Press, 1968.
3. Birkhoff, G.D., “Collected Mathematical Papers”, American Math. Soc., N.Y., 1950.
4. Brillouin, L., “Scientific Uncertainty and Information”, Academic Press, N.Y., 1964.
5. Chandrasekhar, S., “Principles of Stellar Dynamics”, Dover Publ., N.Y., 1960.