@article{JETPL.109.355, title = {}, author = {AlFiky, M. T. and Hamed, A. M.}, journal = {JETP Lett.}, volume = {109}, issue = {6}, pages = {347}, year = {2019}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.1134/S0370274X19060018}, note = {[Pisma v ZhETF 109, 355 (2019)]} }