@article{120064, author = {Miroslav Laitoch}, title = {A modification of the Sturm's theorem on separating zeros of solutions of a linear differential equation of the 2nd order}, journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica}, volume = {17}, year = {1978}, pages = {27-33}, zbl = {0429.34011}, mrnumber = {0554033}, language = {en}, url = {http://dml.mathdoc.fr/item/120064} }
Laitoch, Miroslav. A modification of the Sturm's theorem on separating zeros of solutions of a linear differential equation of the 2nd order. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 17 (1978) pp. 27-33. http://gdmltest.u-ga.fr/item/120064/
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