@article{JETPL.107.99, title = {}, author = {AlFiky, M. T. and Hamed, A. M.}, journal = {JETP Lett.}, volume = {107}, issue = {2}, pages = {91}, year = {2018}, doi = {}, url = {http://jetpletters.ru/ps/dx/10.7868/S0370274X18020042}, note = {[Pisma v ZhETF 107, 99 (2018)]} }