Lobachevskii Journal of Mathematics
Lobachevskii Journal of Mathematics > 2018 > 39 > 1 > 97-103
Lobachevskii Journal of Mathematics > 2018 > 39 > 2 > 165-168
Lobachevskii Journal of Mathematics > 2018 > 39 > 8 > 1140-1147
Lobachevskii Journal of Mathematics > 2018 > 39 > 1 > 97-103
Lobachevskii Journal of Mathematics > 2018 > 39 > 2 > 165-168
Lobachevskii Journal of Mathematics > 2018 > 39 > 8 > 1140-1147