@article{TAM_1979_5_1_a1,
     author = {Vukman \v{C}ovi\'c},
     title = {On a differential principle of higher order for non-holonomic mechanical systems},
     journal = {Theoretical and applied mechanics},
     pages = {14 },
     publisher = {mathdoc},
     volume = {5},
     number = {1},
     year = {1979},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TAM_1979_5_1_a1/}
}