@article{RMH_1981_1981_1_a3,
     author = {Bujalance, Emilio},
     title = {Periodos propios de subgrupos cristalogr\'aficos no eucl{\'\i}deos normales con {\'\i}ndice par.},
     journal = {Revista matem\'atica hispano-americana},
     pages = {121-127},
     publisher = {mathdoc},
     volume = {41},
     number = {5-6},
     year = {1981},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RMH_1981_1981_1_a3/}
}