@article{120073,
author = {Vladim\'\i r Vl\v cek},
title = {On functions describing a distribution of zeros of solutions of an iterated linear differential equation of the fourth order},
journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
volume = {18},
year = {1979},
pages = {103-116},
zbl = {0452.34028},
mrnumber = {0589852},
language = {en},
url = {http://dml.mathdoc.fr/item/120073}
}
Vlček, Vladimír. On functions describing a distribution of zeros of solutions of an iterated linear differential equation of the fourth order. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 18 (1979) pp. 103-116. http://gdmltest.u-ga.fr/item/120073/
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On a distribution of zeros of solutions of a fourth-order iterated linear differential equation, Acta Univ. Palackianae Olomucensis (1977). (1977) | MR 0554040