@article{CLTM_1991_1991_1_a12,
     author = {Etayo Gordejuela, Fernando},
     title = {Jets de superficies.},
     journal = {Collectanea mathematica},
     pages = {171-176},
     publisher = {mathdoc},
     volume = {42},
     number = {2},
     year = {1991},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CLTM_1991_1991_1_a12/}
}