@article{CMUC_1989__30_1_a1,
     author = {\v{C}adek, Martin},
     title = {Oscillatory properties of second order linear differential equations in the complex domain},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {17--21},
     publisher = {mathdoc},
     volume = {30},
     number = {1},
     year = {1989},
     mrnumber = {995697},
     zbl = {0669.34013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1989__30_1_a1/}
}