@article{SIGMA_2015_11_a30,
     author = {Marek Grochowski and Ben Warhurst},
     title = {Invariants and {Infinitesimal} {Transformations} for {Contact} {Sub-Lorentzian} {Structures} on {3-Dimensional} {Manifolds}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2015},
     volume = {11},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2015_11_a30/}
}