This work uses a variational approach to establish the existence of at least two homoclinic solutions for a family of singular Newtonian systems in ℝ³ which are subjected to almost periodic forcing in time variable.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ap114-1-3, author = {Robert Krawczyk}, title = {Homoclinic orbits for an almost periodically forced singular Newtonian system in $\mathbb{R}$$^3$}, journal = {Annales Polonici Mathematici}, volume = {113}, year = {2015}, pages = {29-43}, zbl = {1327.34079}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap114-1-3} }
Robert Krawczyk. Homoclinic orbits for an almost periodically forced singular Newtonian system in ℝ³. Annales Polonici Mathematici, Tome 113 (2015) pp. 29-43. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap114-1-3/