@article{FGGZ10,
author = {H. Fournier and D. Gardy and A. Genitrini and M. Zaionc},
title = {Tautologies over implication with negative literals},
journal = {Mathematical Logic Quarterly},
volume = {56},
number = {4},
year = {2010},
pages = {388--396},
doi = {10.1002/malq.200810053},
ee = {http://dx.doi.org/10.1002/malq.200810053}
}