%0 Journal Article
%T On asymptotic dimension of groups acting on trees
%A G. Bell
%A A. Dranishnikov
%J Mathematics
%D 2001
%I arXiv
%X We prove the following theorem: Let $\pi$ be the fundamental group of a finite graph of groups with finitely generated vertex groups $G_v$ having asdim $G_v\le n$ for all vertices $v$. Then asdim$\pi\le n+1$. This gives the best possible estimate for the asymptotic dimension of an HNN extension and the amalgamated product.
%U http://arxiv.org/abs/math/0111087v2