@article{120054, author = {Stan\v ek, Svatoslav}, title = {A criterion for determining the 2$^nd$ order linear differential equations possessing the central dispersion with the index $n$ equal to $t+\pi$}, journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica}, volume = {16}, year = {1977}, pages = {75-79}, zbl = {0412.34020}, mrnumber = {0594950}, language = {en}, url = {http://dml.mathdoc.fr/item/120054} }
Staněk, Svatoslav. A criterion for determining the 2$^nd$ order linear differential equations possessing the central dispersion with the index $n$ equal to $t+\pi$. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 16 (1977) pp. 75-79. http://gdmltest.u-ga.fr/item/120054/
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