@article{10_4064_ap_19_3_343_345,
     author = {S. Topa},
     title = {Determination of differential concomitants of the first class of a pair of contravariant vectors in a two-dimensional space},
     journal = {Annales Polonici Mathematici},
     pages = {343--345},
     publisher = {mathdoc},
     volume = {19},
     number = {3},
     year = {1967},
     doi = {10.4064/ap-19-3-343-345},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-19-3-343-345/}
}