@article{RRACEFN_1986_1986_1_a4,
     author = {Villanueva, Silvera},
     title = {El espacio {QBU.}},
     journal = {Revista de la Real Academia de Ciencias Exactas, F{\'\i}sicas y Naturales},
     pages = {47-55},
     year = {1986},
     volume = {80},
     number = {1-2},
     language = {es},
     url = {http://geodesic.mathdoc.fr/item/RRACEFN_1986_1986_1_a4/}
}