@book{ Solr-96505, title = {Contributions to the theory of nonlinear oscillations. 5}, series = {Annals of mathematics studies ;}, author = {Cesari, L.}, editor = {Cesari, L.}, editor = {Lasalle, J. P.}, address = {Princeton, NJ}, publisher = {Princeton University Pr.}, year = {1960}, note = {englisch}, }