@book{ECDL_2,
author = "Sidiropoulos, Nikolaos and Hatzigeorgiu, Nick",
publisher = "LibrisTech ΑΕ",
title = ""Advanced {S}preadsheets", {E}uropean {C}omputer {D}riving {L}icence (ECDL) {S}eries ",
year = "2004",
}