@article{EXMATH_1993_1993_1_a5,
     author = {Flor{\'\i}a, Luis},
     title = {Sobre la derivaci\'on de un conjunto can\'onico de primer orden de elementos hiperb\'olicos de tipo {Delaunay.}},
     journal = {Extracta mathematicae},
     pages = {49-53},
     publisher = {mathdoc},
     volume = {8},
     number = {1},
     year = {1993},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EXMATH_1993_1993_1_a5/}
}