@article{EUG_1987_17_a18, author = { and Arthur Engel}, title = {A\ensuremath{\nu}\ensuremath{\iota}\ensuremath{\sigma}\'{o}\ensuremath{\tau}\ensuremath{\eta}\ensuremath{\tau}\ensuremath{\varepsilon}\ensuremath{\varsigma}}, journal = {E\ensuremath{\upsilon}\ensuremath{\kappa}\ensuremath{\lambda}\ensuremath{\varepsilon}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma} \ensuremath{\Gamma}}, pages = {117--143}, year = {1987}, volume = {17}, language = {gr}, url = {http://geodesic.mathdoc.fr/item/EUG_1987_17_a18/} }