@article{FORUM_1993__5_3_141698,
     author = {Sette Diop},
     title = {Closedness of morphisms of differential algebraic sets. {Applications} to system theory.},
     journal = {Forum mathematicum},
     pages = {33--48},
     publisher = {mathdoc},
     volume = {5},
     number = {3},
     year = {1993},
     zbl = {0766.93011},
     url = {http://geodesic.mathdoc.fr/item/FORUM_1993__5_3_141698/}
}