@article{CMUC_1989__30_4_a17,
     author = {Kratochv{\'\i}l, Jan},
     title = {Perfect codes and two-graphs},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {755--760},
     publisher = {mathdoc},
     volume = {30},
     number = {4},
     year = {1989},
     mrnumber = {1045906},
     zbl = {0693.05060},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1989__30_4_a17/}
}