Real Computational Universality: The Word Problem for a class of groups with infinite presentation.

Klaus Meer Martin Ziegler Real Computational Universality: The Word Problem for a class of groups with infinite presentation. 2006 Algorithms and Complexity for Continuous Problems http://drops.dagstuhl.de/opus/volltexte/2007/877 conf/dagstuhl/2006P6391 db/conf/dagstuhl/P6391.html#MeerZ06