@inproceedings{1041481,
    title = "The opsis project: materialized views for data warehouses and the web",
    author = "Roussopoulos, Nick and Kotidis, Yannis and Labrinidis, Alexandros and Σισμάνης, Γιάννης",
    year = "2001",
    pages = "217-226",
    publisher = "Εκδοτικός Οργανισμός Λιβάνη",
    booktitle = "8th Panhellenic Conference in Informatics Proceedings (Volume 1)"
}