@article{Białynicki-Birula:1980,
  author  = "I. Białynicki-Birula and V. Cao Long",
  title   = "Energy levels of dressed atoms and resonance phenomena",
  journal = "Acta Physica Polonica A",
  volume  = "Vol. 57",
  number  = "no 4",
  pages   = "599--611",
  year    = "1980",
}