Zoltán Fülöp Armin Kühnemann Heiko Vogler Linear deterministic multi bottom-up tree transducers. 276-287 2005 347 Theor. Comput. Sci. 1-2 http://dx.doi.org/10.1016/j.tcs.2005.07.025 db/journals/tcs/tcs347.html#FulopKV05