@article{Kondej:2012,
  author  = "S. Kondej and J. Vaz, Jr.",
  title   = "Fractional Schrödinger operator with delta potential localized on circle",
  journal = "Journal of Mathematical Physics",
  volume  = "Vol. 53",
  pages   = "033503-1-- 11",
  year    = "2012",
}