Undecidability of first-order intuitionistic and modal logics with two variables
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\begin{bibtex} @article{DBLP:journals/bsl/KontchakovKZ05,
author = {Roman Kontchakov and
Agi Kurucz and
Michael Zakharyaschev},
title = {Undecidability of first-order intuitionistic and modal logics
with two variables},
journal = {Bulletin of Symbolic Logic},
volume = {11},
number = {3},
year = {2005},
pages = {428-},
ee = {http://www.math.ucla.edu/$\sim$asl/bsl/1103/1103-006.ps},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
\end{bibtex}
