@article{10_2140_agt_2009_9_1413,
     author = {Paternain, Gabriel P},
     title = {Helicity and the {Ma\~n\'e} critical value},
     journal = {Algebraic and Geometric Topology},
     pages = {1413--1422},
     year = {2009},
     volume = {9},
     number = {3},
     doi = {10.2140/agt.2009.9.1413},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2009.9.1413/}
}