@article{ITA_1991__25_3_205_0,
     author = {Bossut, F. and Warin, B.},
     title = {On a code problem concerning planar acyclic graphs},
     journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications},
     pages = {205--218},
     publisher = {EDP-Sciences},
     volume = {25},
     number = {3},
     year = {1991},
     mrnumber = {1119041},
     zbl = {0727.68053},
     language = {en},
     url = {http://archive.numdam.org/item/ITA_1991__25_3_205_0/}
}