@article{articlec1f55654,
title   = {Unitarity and vacuum deformation in QED with critical potential steps},
author = {Gavrilov, S. P. and Shishmarev, A. A. and Gitman, Dmitri Maximovitch},
year = {2016},
doi = {10.1103/PhysRevD.93.105040},
journal   = {PHYSICAL REVIEW D}
}