@inproceedings{
    kmcpm92,
    author = {Kilpel{\"a}inen, P. and Mannila, Heikki},
    pages = "202-214",
    booktitle = "Combinatorial Pattern Matching, Third Workshop",
    year = "1992",
    editors = "A. Apostolico et al.",
    title = "Grammatical tree matching"
}