@techreport{
    prz:swi:97,
    author = "Przepiórkowski, Adam and Świdziński, Marek",
    title = "{P}olish Verbal Negation Revisited: A Metamorphosis vs. {HPSG} Account",
    url = "http://nlp.ipipan.waw.pl/~adamp/Papers/1997-829/",
    year = "1997",
    number = "829",
    address = "Warsaw",
    type = "{IPI PAN} Research Report",
    institution = "Institute of Computer Science, Polish Academy of Sciences"
}