Kovalev, Y. Yurievich Max Planck Institute for Radio Astronomy, Max Planck Society;
Kovalev, Y., Kovalev, Y. A., Nizhelsky, N. A., Kovalev, Y. Y., Troitsky, S. V., Zhekanis, G. V., et al. (2022). The keys by Nikolai Kardashev and Yuri Parijskij to the Nature of Active Galactic Nuclei. In The Multifaceted Universe: Theory and Observations - 2022 (pp. 27).