@article{10_21136_CMJ_1984_101984,
     author = {Krupka, Demeter and Mikol\'a\v{s}ov\'a, V\v{e}ra},
     title = {On the uniqueness of some differential invariants: $d$, $[,]$, $\nabla$},
     journal = {Czechoslovak Mathematical Journal},
     pages = {588--597},
     publisher = {mathdoc},
     volume = {34},
     number = {4},
     year = {1984},
     doi = {10.21136/CMJ.1984.101984},
     mrnumber = {764440},
     zbl = {0571.53009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1984.101984/}
}