@article{EUG_1987_17_a0,
     author = {Y. G. Sficas},
     title = {Retarded {Actions} on {Oscillations}},
     journal = {E\ensuremath{\upsilon}\ensuremath{\kappa}\ensuremath{\lambda}\ensuremath{\varepsilon}\ensuremath{\acute\iota}\ensuremath{\delta}\ensuremath{\eta}\ensuremath{\varsigma} \ensuremath{\Gamma}},
     pages = {1--10},
     year = {1987},
     volume = {17},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/EUG_1987_17_a0/}
}