@article{Girouard_2007, title={Relative homological linking in critical point theory}, volume={30}, url={https://apcz.umk.pl/TMNA/article/view/TMNA.2007.026}, abstractNote={A relative homological linking of pairs is proposed. It is shown to imply homotopical linking, as well as earlier non-relative notion of homological linkings. Using Morse theory we prove a simple "homological linking principle", thereby generalizing and simplifying many well known results in critical point theory.}, number={2}, journal={Topological Methods in Nonlinear Analysis}, author={Girouard, Alexandre}, year={2007}, month={Dec.}, pages={211–221} }