@article{AIHPA_1979__30_2_143_0,
     author = {Benenti, Sergio and Francaviglia, Mauro},
     title = {Canonical forms for $\mathcal {S}_{n-3}$-structures in pseudo-riemannian manifolds},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {143--157},
     publisher = {Gauthier-Villars},
     volume = {30},
     number = {2},
     year = {1979},
     mrnumber = {535370},
     zbl = {0459.53019},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1979__30_2_143_0/}
}