@article{RRACEFN_1987_1987_1_a6,
     author = {Gil Alvarez, M. A. and  Brezmes Brezmes, T. and  Gil \'Alvarez, P.},
     title = {La varianza, como medida de inquietud, en el caso bidimensional.},
     journal = {Revista de la Real Academia de Ciencias Exactas, F{\'\i}sicas y Naturales },
     pages = {91-101},
     publisher = {mathdoc},
     volume = {81},
     number = {1},
     year = {1987},
     language = {es},
     url = {http://geodesic.mathdoc.fr/item/RRACEFN_1987_1987_1_a6/}
}