@conference{7134,
  author = {T. Hellmuth and G. Leuchs and S. Smith and H. Walther},
  title = {Angular Distribution of Photoelectrons in Multiphoton Ionization},
  year = {1981},
  publisher = {Budapest : Central Research Institute for Physics},
  address = {Budapest, Hungary},
  note = {JILA Pub. 2167},
}