@article{EXMATH_1992_1992_1_a18,
     author = {Calder\'on, C. and Z\'arate, M. J.},
     title = {El n\'umero de anillos semisimples de orden como m\'aximo x.},
     journal = {Extracta mathematicae},
     pages = {144-147},
     publisher = {mathdoc},
     volume = {7},
     number = {2-3},
     year = {1992},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EXMATH_1992_1992_1_a18/}
}