1. Yu. G. Ignat’ev, Russ. Phys. J., 56, No. 6, 693–706 (2013).
2. Yu. G. Ignat’ev, Sov. Phys. J., 29, No. 2, 104–108 (1986).
3. Yu. G. Ignat’ev, Prostr., Vremya Fund. Vzaimod., No. 2, 5–10 (2013).
4. Yu. Ignatyev, arXiv:1306.3633v1 [gr-qc] 13 June 2013.
5. Yu. G. Ignatyev, arXiv:1308.1569[gr-qc] 7 August 2013.