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Let X be a locally finite tree, and let G = Aut(X). Then G is a locally compact group. A non-uniform X-lattice is a discrete subgroup Γ ≤ G such that the quotient graph of groups Γ\\X is infinite but has finite covolume, and a non-uniform G-lattice is a discrete subgroup Λ such that Λ\G is not compact yet has a finite G-invariant measure. We show that if X has a unique end and if G contains a n...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1954
ISSN: 0002-9939
DOI: 10.2307/2031872