1. L. D. Landau and E. M. Lifshitz, Quantum Mechanics (Butterworth-Heinemann, Oxford, 2005), p. 677; L. E. Ballentine, Quantum Mechanics. A Modern Development (World Scientific, Singapore, 2003), p. 658.
2. L. D. Landau and E. M. Lifshitz, The Classical Theory of Fields (Butterworth-Heinemann, Oxford, 2000), p. 431.
3. E. Schröbinger, Collected Papers on Wave Mechanics (AMS Chelsea Publishing, Providence, Rhode Island, 1982), p. 207.
4. P. A. M. Dirac, The Principles of Quantum Mechanics (Oxford University Press, Oxford, 1982), p. 316; L. I. Schiff, Quantum Mechanics (McGraw-Hill, London, 1968), p. 538.
5. A. O. Barut, “Quantum theory of single events: localized de Broglie wavelets, Schröbinger waves and classical trajectories,” Found. Phys. 20(10), 1223–1240 (1990).