@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/