Zaytseva, T. B.
Medvedeva, N. G.
Article History
Received: 12 February 2019
Revised: 27 February 2019
Accepted: 29 March 2019
First Online: 6 August 2019
COMPLIANCE WITH ETHICAL STANDARDS
: The authors declare that they have no conflict of interest. This article does not contain any studies involving animals or human participants performed by any of the au-thors.