@article{CMUC_2001_42_2_a11,
     author = {Tardif, Claude},
     title = {The chromatic number of the product of two graphs is at least half the minimum of the fractional chromatic numbers of the factors},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {353--355},
     year = {2001},
     volume = {42},
     number = {2},
     mrnumber = {1832153},
     zbl = {1050.05057},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_2001_42_2_a11/}
}