@article{Leyser2012a,
  author = "T. B. Leyser and F. Waldemarsson and S. C. Buchert",
  title = "Plasma angular momentum effects and twisted incoherent scatter radar beams",
  year =  2012 ,
  journal = "Radio Sci.",
  volume = 47,
  number = 5,
  keywords = "amisr, pfisr",
  doi = "10.1029/2011RS004819"
}