@inproceedings{Hamann2003,
  author    = {Silke Hamann},
  title     = {Postalveolar fricatives in Slavic languages as retroflexes},
  url       = {http://user.phil-fak.uni-duesseldorf.de/~hamann/Hamann2002SlavicRet.pdf},
  year      = {2003},
}