@article{AFM_1981_6_1_a10,
     author = {Arto Salomaa},
     title = {On color-families of graphs},
     journal = {Annales Fennici Mathematici},
     pages = {135--148},
     year = {1981},
     volume = {6},
     number = {1},
     doi = {10.5186/aasfm.1981.0619},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1981.0619/}
}