@article{bwmeta1.element.bwnjournal-article-fmv116i1p9bwm,
author = {T. McKee},
title = {Validity up to complementation in graph theory},
journal = {Fundamenta Mathematicae},
volume = {115},
year = {1983},
pages = {93-98},
zbl = {0546.05060},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-fmv116i1p9bwm}
}
McKee, T. Validity up to complementation in graph theory. Fundamenta Mathematicae, Tome 115 (1983) pp. 93-98. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-fmv116i1p9bwm/