@article{MR_1980_18_a5,
     author = {N. K\ensuremath{\alpha}\ensuremath{\sigma}\ensuremath{\tau}\ensuremath{\acute\alpha}\ensuremath{\nu}\ensuremath{\eta}\ensuremath{\varsigma}},
     title = {M\ensuremath{\iota}\ensuremath{\chi}\ensuremath{\alpha}\ensuremath{\acute\eta}\ensuremath{\lambda} {\ensuremath{\Sigma}\ensuremath{\tau}\ensuremath{\varepsilon}\ensuremath{\varphi}\ensuremath{\alpha}\ensuremath{\nu}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma}.} {\'{}E\ensuremath{\nu}\ensuremath{\alpha}\ensuremath{\varsigma}} {\ensuremath{\Pi}\ensuremath{\rho}\ensuremath{\omega}\ensuremath{\tau}o\ensuremath{\pi}\'{o}\ensuremath{\rho}o\ensuremath{\varsigma}} {M\ensuremath{\varepsilon}\ensuremath{\lambda}\ensuremath{\varepsilon}\ensuremath{\tau}\ensuremath{\eta}\ensuremath{\tau}\ensuremath{\acute\eta}\ensuremath{\varsigma}} \ensuremath{\tau}\ensuremath{\eta}\ensuremath{\varsigma} {I\ensuremath{\sigma}\ensuremath{\tau}o\ensuremath{\rho}\ensuremath{\acute\iota}\ensuremath{\alpha}\ensuremath{\varsigma}} \ensuremath{\tau}\ensuremath{\eta}\ensuremath{\varsigma} {E\ensuremath{\pi}\ensuremath{\iota}\ensuremath{\sigma}\ensuremath{\tau}\ensuremath{\acute\eta}\ensuremath{\mu}\ensuremath{\eta}\ensuremath{\varsigma}.}},
     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 = {3--6},
     year = {1980},
     volume = {18},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/MR_1980_18_a5/}
}