1. L. D. Landau and Е. М. Lifshits, Quantum Mechanics. Theoretical Physics, Vol. III [in Russian], Nauka, Moscow (1982).
2. É. A. Arinshtein and V. G. Bagrov, Russ. Phys. J., 8, 783–791 (2008).
3. V. G. Bagrov, M. C. Baldiotti, D. M. Gitman, and I. V. Shirokov, J. Math. Phys., 43, 2284–2305 (2002).
4. M. Moshansky, The Harmonic Oscillator in Modern Physics: From Atoms to Quarks, Gordon and Breach, New York (1969).
5. H. C. Brinkman, Applications of Spinor Invariants in Atomic Physics, North-Holland Pub. Co, Amsterdam (1956).