@article{EUG_1999_52_a7,
     author = {K\ensuremath{\alpha}\ensuremath{\varphi}o\ensuremath{\acute\upsilon}\ensuremath{\sigma}\ensuremath{\eta} \ensuremath{\Sigma}\'{o}\ensuremath{\nu}\ensuremath{\iota}\ensuremath{\alpha}},
     title = {O\ensuremath{\iota} \ensuremath{\iota}\ensuremath{\delta}\ensuremath{\acute\epsilon}\ensuremath{\varepsilon}\ensuremath{\varsigma} \ensuremath{\tau}\ensuremath{\omega}\ensuremath{\nu} \ensuremath{\pi}\ensuremath{\alpha}\ensuremath{\iota}\ensuremath{\delta}\ensuremath{\iota}\ensuremath{\acute\omega}\ensuremath{\nu} \ensuremath{\tau}\ensuremath{\eta}\ensuremath{\varsigma} {E΄\ensuremath{\kappa}\ensuremath{\alpha}\ensuremath{\iota}} {\ensuremath{\Sigma}T΄\ensuremath{\tau}\ensuremath{\acute\alpha}\ensuremath{\xi}\ensuremath{\eta}\ensuremath{\varsigma}} \ensuremath{\tau}o\ensuremath{\upsilon} {\ensuremath{\Delta}\ensuremath{\eta}\ensuremath{\mu}o\ensuremath{\tau}\ensuremath{\iota}\ensuremath{\kappa}o\ensuremath{\acute\upsilon}} \ensuremath{\gamma}\ensuremath{\iota}\ensuremath{\alpha} \ensuremath{\tau}\ensuremath{\eta}\ensuremath{\nu} \ensuremath{\acute\epsilon}\ensuremath{\nu}\ensuremath{\nu}o\ensuremath{\iota}\ensuremath{\alpha} \ensuremath{\tau}\ensuremath{\eta}\ensuremath{\varsigma} {\ensuremath{\Pi}\ensuremath{\iota}\ensuremath{\theta}\ensuremath{\alpha}\ensuremath{\nu}\'{o}\ensuremath{\tau}\ensuremath{\eta}\ensuremath{\tau}\ensuremath{\alpha}\ensuremath{\varsigma}.}},
     journal = {E\ensuremath{\upsilon}\ensuremath{\kappa}\ensuremath{\lambda}\ensuremath{\varepsilon}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma} \ensuremath{\Gamma}},
     pages = {31--41},
     year = {1999},
     volume = {52},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/EUG_1999_52_a7/}
}