@article{MR_1975_2_a65,
     author = {M. Z\ensuremath{\acute\eta}\ensuremath{\beta}\ensuremath{\alpha}\ensuremath{\varsigma} and  \ensuremath{\Pi}. \ensuremath{\Sigma}o\ensuremath{\upsilon}\ensuremath{\gamma}\ensuremath{\alpha}\ensuremath{\nu}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma}},
     title = {\ensuremath{\Theta}\ensuremath{\acute\epsilon}\ensuremath{\mu}\ensuremath{\alpha}\ensuremath{\tau}\ensuremath{\alpha} {\ensuremath{\Delta}\ensuremath{\iota}\ensuremath{\alpha}\ensuremath{\gamma}\ensuremath{\omega}\ensuremath{\nu}\ensuremath{\iota}\ensuremath{\sigma}\ensuremath{\mu}\ensuremath{\acute\omega}\ensuremath{\nu}}},
     journal = {M\ensuremath{\alpha}\ensuremath{\theta}\ensuremath{\eta}\ensuremath{\mu}\ensuremath{\alpha}\ensuremath{\tau}\ensuremath{\iota}\ensuremath{\kappa}\ensuremath{\acute\eta} E\ensuremath{\pi}\ensuremath{\iota}\ensuremath{\theta}\ensuremath{\varepsilon}\ensuremath{\acute\omega}\ensuremath{\rho}\ensuremath{\eta}\ensuremath{\sigma}\ensuremath{\eta}},
     pages = {6--10},
     year = {1975},
     volume = {2},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/MR_1975_2_a65/}
}