@article{10881,
  author = {L. Rosenberg},
  title = {Sum rule and classical limit for scattering in a low-frequency laser field},
  year = {1979},
  journal = {Physical Review A},
  volume = {20},
  pages = {1352-1358},
  month = {Jan-10-1979},
  issn = {0556-2791},
  url = {http://link.aps.org/doi/10.1103/PhysRevA.20.1352},
  doi = {10.1103/PhysRevA.20.1352},
}