@article{BAG_1991__31_138471,
     author = {V. Boju and L. Funar},
     title = {Generalized area in {Minkowskian} spaces},
     journal = {Beitr\"age zur Algebra und Geometrie},
     pages = {33--38},
     year = {1991},
     volume = {31},
     zbl = {0737.51018},
     url = {http://geodesic.mathdoc.fr/item/BAG_1991__31_138471/}
}