@article{AIHPA_1980__33_2_121_0,
     author = {Jantzen, Robert T.},
     title = {Conformal geometry and spatially homogeneous cosmology},
     journal = {Annales de l'institut Henri Poincar\'e. Section A, Physique Th\'eorique},
     pages = {121--146},
     publisher = {Gauthier-Villars},
     volume = {33},
     number = {2},
     year = {1980},
     mrnumber = {605193},
     zbl = {0474.53057},
     language = {en},
     url = {http://www.numdam.org/item/AIHPA_1980__33_2_121_0/}
}