@article{MASLO_1999_49_5_a3,
     author = {Chao, Dao Qui and Krupka, Demeter},
     title = {3rd order differential invariants of coframes},
     journal = {Mathematica slovaca},
     pages = {563--576},
     year = {1999},
     volume = {49},
     number = {5},
     mrnumber = {1746900},
     zbl = {0962.53012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MASLO_1999_49_5_a3/}
}