@article{MR_1977_8_a16,
     author = {M. \ensuremath{\Lambda}\ensuremath{\acute\alpha}\ensuremath{\mu}\ensuremath{\pi}\ensuremath{\rho}o\ensuremath{\upsilon} and  M. K\ensuremath{\alpha}\ensuremath{\tau}\ensuremath{\sigma}o\ensuremath{\pi}\ensuremath{\rho}\ensuremath{\iota}\ensuremath{\nu}\ensuremath{\acute\alpha}\ensuremath{\kappa}\ensuremath{\eta}\ensuremath{\varsigma}},
     title = {O {E\ensuremath{\upsilon}\ensuremath{\kappa}\ensuremath{\lambda}\ensuremath{\varepsilon}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma}} {\ensuremath{\Gamma}΄} \ensuremath{\sigma}\ensuremath{\alpha}\ensuremath{\varsigma} \ensuremath{\alpha}\ensuremath{\pi}\ensuremath{\alpha}\ensuremath{\nu}\ensuremath{\tau}\ensuremath{\acute\alpha} - {A\ensuremath{\lambda}\ensuremath{\lambda}\ensuremath{\eta}\ensuremath{\lambda}o\ensuremath{\gamma}\ensuremath{\rho}\ensuremath{\alpha}\ensuremath{\varphi}\ensuremath{\acute\iota}\ensuremath{\alpha}}},
     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 = {56--64},
     year = {1977},
     volume = {8},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/MR_1977_8_a16/}
}