Unfortunately, the equation (3.13) of the original version of this paper contained a typo. The correct relation reads as follows (Formula presented.) Here the correct value of the power 1/2 eliminates the typo (−1/2) in the earlier published version of the paper. It was a typo—not a mistake: i.e. all other relations were correct. Unfortunately the following Acknowledgments are missing in the original article: Acknowledgements The research was funded by the Ministry of Education and Science of the Russian Federation in the Program to increase the competitiveness of Peoples’ Friendship University (RUDN University) among the world’s leading research and education centers in the 2016–2020 and by the Russian Foundation for Basic Research, Grant Nr. 16-02-00602. © 2016, The Author(s).