@article{bwmeta1.element.bwnjournal-article-zmv7i3p235, author = {A. Rybarski}, title = {Angen\"aherte Schwingungsfrequenzformeln f\"ur konservative Systeme. I}, journal = {Applicationes Mathematicae}, volume = {7}, year = {1964}, pages = {235-253}, zbl = {0129.16804}, language = {deu}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-zmv7i3p235} }
Rybarski, A. Angenäherte Schwingungsfrequenzformeln für konservative Systeme. I. Applicationes Mathematicae, Tome 7 (1964) pp. 235-253. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-zmv7i3p235/