@article{PM_1992_1992_1_a40,
     author = {Dou, Albert},
     title = {El {"Corolario} {II"} a la proposici\'on {XXIII} del {Euclides} de {Saccheri.}},
     journal = {Publicacions matem\`atiques},
     pages = {533-540},
     year = {1992},
     volume = {36},
     number = {2A},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PM_1992_1992_1_a40/}
}