@article{EXMATH_1994_1994_1_a4,
     author = {Benkiran, Taoufiq},
     title = {Problema de perturbaci\'on con cambio de tipo {(I).}},
     journal = {Extracta mathematicae},
     pages = {37-41},
     publisher = {mathdoc},
     volume = {9},
     number = {1},
     year = {1994},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/item/EXMATH_1994_1994_1_a4/}
}