@article{alexov1993nonreciprocal,
  author = "E. G. Alexov and S. T. Ivanov",
  title = "Nonreciprocal effects in a plasma waveguide",
  year = 1993,
  journal = "IEEE transactions on plasma science",
  publisher = "IEEE",
  volume = 21,
  number = 2,
  pages = "254-257"
}