@article{Corona_Giambò_Giannoni_Piccione_2023, title={On the relative category in the brake orbits problem}, volume={61}, url={https://apcz.umk.pl/TMNA/article/view/42926}, DOI={10.12775/TMNA.2022.057}, abstractNote={In this paper %dedicated to the memory of Edward Fadell and Sufian Husseini
we show how the notion of the Lusternik-Schnirelmann relative category can be used
to study a multiplicity problem for brake orbits in a potential well
which is homeomorphic to the $N$-dimensional unit disk.
The estimate of the relative category of the set of chords with endpoints on the
$(N-1)$-unit sphere was shown to the third author by
Fadell and Husseini while he was visiting the University of Wisconsin at Madison.}, number={1}, journal={Topological Methods in Nonlinear Analysis}, author={Corona, Dario and Giambò, Roberto and Giannoni, Fabio and Piccione, Paolo}, year={2023}, month={Mar.}, pages={199–215} }