@article{120175,
author = {Vladim\'\i r Vl\v cek},
title = {On the focal points of solutions of a certain fourth order differential equation},
journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica},
volume = {25},
year = {1986},
pages = {97-115},
zbl = {0643.34040},
mrnumber = {918371},
language = {en},
url = {http://dml.mathdoc.fr/item/120175}
}
Vlček, Vladimír. On the focal points of solutions of a certain fourth order differential equation. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 25 (1986) pp. 97-115. http://gdmltest.u-ga.fr/item/120175/
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