author: Bertachas, Ioannis_or_Sakellariou, Ilias_or_Kefalas, Petros_or_Perivolaropoulos, Leandros_or_Tzanakis, Georgios_or_Περιβολαρόπουλος, Λέανδρος__elsubjectTerm: I. MATHEMATICS AND COMPUTER SCIENCE_or_II. NATURAL SCIENCES AND AGRICULTURAL SCIENCESlang: el