1. L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics [in Russian], Vol. 3, Quantum Mechanics: Non-Relativistic Theory, Nauka, Moscow (2004); English transl. prev. ed., Pergamon, London (1958).
2. V. de Alfaro and T. Regge, Potential Scattering, North-Holland, Amsterdam (1965).
3. J. R. Taylor, Scattering Theory, Wiley, New York (1972).
4. F. Calogero, Variable Phase Approach to Potential Scattering, Acad. Press, New York (1967).
5. V. V. Babikov, Method of Phase Functions in Quantum Mechanics [in Russian], Nauka, Moscow (1976).