@article{GDZPPN002065088, title = {Some existence theorems for closed geodesics.}, journal = {Commentarii mathematici Helvetici}, volume = {58}, year = {1983}, pages = {416-432}, zbl = {0532.53034}, url = {http://dml.mathdoc.fr/item/GDZPPN002065088} }
Ballmann, W.; Thorbergsson, G. Some existence theorems for closed geodesics.. Commentarii mathematici Helvetici, Tome 58 (1983) pp. 416-432. http://gdmltest.u-ga.fr/item/GDZPPN002065088/