@article{RRACEFN_1990_1990_1_a12,
     author = {Criado, F.},
     title = {Sobre el teorema de las dos alternativas.},
     journal = {Revista de la Real Academia de Ciencias Exactas, F{\'\i}sicas y Naturales},
     pages = {429-433},
     year = {1990},
     volume = {84},
     number = {3},
     language = {es},
     url = {http://geodesic.mathdoc.fr/item/RRACEFN_1990_1990_1_a12/}
}