1. L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics [in Russian], Vol. 3, Quantum Mechanics: Non-Relativistic Theory, Nauka, Moscow (1974); English transl. prev. ed., Pergamon, London (1958).
2. S. Flügge, Practical Quantum Mechanics, Springer, Berlin (1974).
3. V. de Alfaro and F. Regge, Potential Scattering, North-Holland, Amsterdam (1965).
4. J. R. Taylor, Scattering Theory: Quantum Theory of Nonrelativistic Collisions, Wiley, New York (1972).
5. V. V. Babikov, Method of Phase Functions in Quantum Mechanics [in Russian], Nauka, Moscow (1976).