%0 Journal Article
%A Barvínek, Erich
%T Quadratic phases of differential equations $y''=q(t)y$
%J Archivum mathematicum
%D 1972
%P 63-78
%V 8
%N 2
%U http://geodesic.mathdoc.fr/item/ARM_1972_8_2_a0/
%G en
%F ARM_1972_8_2_a0