The;
Blagoveshchensk;
State;
Pedagogical;
University,;
Blagoveshchensk,;
Russia;
Institute;
of;
Physics,;
St.;
Petersburg;
State;
University,;
Petrodvorets,;
Russia;
The;
Blagoveshchensk;
State;
Pedagogical;
University,;
Blagoveshchensk,;
Russia;
The;
Blagoveshchensk;
State;
Pedagogical;
University,;
Blagoveshchensk,;
Russia;