1. Shklovskii, I. S. Astron. Zh. 37, 256–262 (1960).
2. Shklovskii, I. S. Astron. Zh. 37, 369–378 (1960).
3. Urošević, D. Astrophys. Space Sci. 354, 541–552 (2014).
4. Pacholczyk, A. G. Radio Astrophysics: Nonthermal Processes in Galactic and Extragalactic Sources (Freeman, 1970).
5. Pavlović, M. Z. et al. Astrophys. J. 852, 84 (2018).