@article{RMI_1990_1990_1_a7,
     author = {Youssfi, Abdellah},
     title = {Continuidad, en espacios de {Sobolev,} de ciertos operadores paradiferenciales.},
     journal = {Revista matem\'atica iberoamericana},
     pages = {125-140},
     publisher = {mathdoc},
     volume = {6},
     number = {3-4},
     year = {1990},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/item/RMI_1990_1990_1_a7/}
}