@article{RACSAM_2003_2003_1_a13,
     author = {Pedregal, Pablo},
     title = {Sobre la estructura de gradientes sim\'etricos 2 x 2.},
     journal = {Revista de la Real Academia de Ciencias Exactas, F{\'\i}sicas y Naturales. Matem\'aticas},
     pages = {119-131},
     year = {2003},
     volume = {97},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RACSAM_2003_2003_1_a13/}
}