@article{1103941279, author = {Mather, John N.}, title = {Amount of rotation about a point and the Morse index}, journal = {Comm. Math. Phys.}, volume = {92}, number = {3}, year = {1984}, pages = { 141-153}, language = {en}, url = {http://dml.mathdoc.fr/item/1103941279} }
Mather, John N. Amount of rotation about a point and the Morse index. Comm. Math. Phys., Tome 92 (1984) no. 3, pp. 141-153. http://gdmltest.u-ga.fr/item/1103941279/