@article{10_21136_CMJ_1987_102153,
     author = {Grammatikopoulos, Myron K. and Ladas, G. and Sficas, Yiannis G.},
     title = {Necessary and sufficient conditions for oscillation of delay equations with constant coefficients},
     journal = {Czechoslovak Mathematical Journal},
     pages = {262--270},
     publisher = {mathdoc},
     volume = {37},
     number = {2},
     year = {1987},
     doi = {10.21136/CMJ.1987.102153},
     mrnumber = {882598},
     zbl = {0634.34052},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1987.102153/}
}