- ./edge-fig.ps

A class of automorphism groups of polygonal complexes, Quart. J. Math 52 (2001), 231-247.

- ./invol2.ps

Some infinite groups generated by involutions have Kazhdan's property (T), Forum Mathematicum 13 (2001), 741-755. - ./graf2.ps

Estimates for homological dimension of configuration spaces of graphs, Colloquium Math. 89 (2001), 69-79. - ./grpr.dvi

(with Tadeusz Januszkiewicz) Commensurability of graph products, Algebraic and Geometric Topology 1 (2001), 587-603.