@article{BAG_1985__20_138318,
     author = {L. Staiger},
     title = {Maximality of codes in free monoids},
     journal = {Beitr\"age zur Algebra und Geometrie},
     pages = {191--196},
     publisher = {mathdoc},
     volume = {20},
     year = {1985},
     zbl = {0573.20063},
     url = {http://geodesic.mathdoc.fr/item/BAG_1985__20_138318/}
}