1. J.R. Schrieffer, Theory of Superconductivity (Westview Press, Boulder, 1999). https://doi.org/10.1201/9780429495700
2. M. Tinkham, Introduction to Superconductivity (Dover Publications, Garden City, 2004)
3. J. Bardeen, Phys. Rev. Lett. 9, 147 (1962). https://doi.org/10.1103/PhysRevLett.9.147
4. J. Josephson, Phys. Lett. 1, 251 (1962). https://doi.org/10.1016/0031-9163(62)91369-0
5. A.F. Andreev, Soviet-Phys. JETP 19, 1228 (1964)