@article{01119069,
title = {An improved bound on the minimal number of edges in color-critical graphs.},
journal = {The Electronic Journal of Combinatorics [electronic only]},
volume = {5},
year = {1998},
zbl = {0885.05063},
language = {en},
url = {http://dml.mathdoc.fr/item/01119069}
}
Krivelevich, Michael. An improved bound on the minimal number of edges in color-critical graphs.. The Electronic Journal of Combinatorics [electronic only], Tome 5 (1998) . http://gdmltest.u-ga.fr/item/01119069/