@article{JETPL.110.727, title = {}, author = {, and Belavin, A.}, journal = {JETP Lett.}, volume = {110}, issue = {11}, pages = {711}, year = {2019}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.1134/S0370274X19230024}, note = {[Pisma v ZhETF 110, 727 (2019)]} }