@ARTICLE{Voronkov99,
AUTHOR = {Voronkov, Andrei},
TITLE = {The ground-negative fragment of first-order logics is $\pi^p_2$-complete},
JOURNAL = {The Journal of Symbolic Logic},
PUBLISHER = {Association for Symbolic Logic},
YEAR = {1999},
NUMBER = {3},
VOLUME = {64},
PAGES = {984--990},
MONTH = {September},
}
Entry last modified by Uwe Brahm, 03/12/2010