1. A. Angot,Compléments de mathématiques. CNET, Paris 1961.
2. M. Ash,Nuclear reactor kinetics. McGraw-Hill Book Co. New York 1979, 137?139.
3. P. Hagedorn,Non-linear oscillations. Clarendon Press, Oxford 1981.
4. G. A. Korn and T. M. Korn,Mathematical handbook for scientists and engineers. McGraw-Hill Book Co., New York 1961.
5. G. S. Lellouche,Reactor-kinetics stability criteria. Nucl. Sci. & Engng.,24, p. 72 (1966).