@inproceedings{1041972,
    title = "Proving copyright ownership using hard instances of computationally intractable problems",
    author = "Armeni, S. and Christodoulakis, D. and Kostopoulos, I. and Stamatiou, Y. C. and Xenos, Michalis",
    year = "2001",
    pages = "137-145",
    publisher = "Εκδοτικός Οργανισμός Λιβάνη",
    booktitle = "8th Panhellenic Conference in Informatics Proceedings (Volume 2)"
}