@article{JRAM_1991__419_153342,
     author = {T. Bartsch and M. Clapp and D. Puppe},
     title = {A mountain pass theorem for actions of compact {Lie} groups.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {55--66},
     publisher = {mathdoc},
     volume = {419},
     year = {1991},
     zbl = {0731.58016},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1991__419_153342/}
}