@TechReport{AIB-2006-13,
  author =	 {Wong Karianto and Christof L{\"o}ding},
  title =	 {Unranked Tree Automata with Sibling Equalities and
                  Disequalities},
  institution =	 {RWTH Aachen},
  year =	 2006,
  number =	 {AIB-2006-13},
  month =	 {October},
  url =		 {http://aib.informatik.rwth-aachen.de/2006/2006-13.pdf},
  keywords =	 {(unranked) tree automata, monadic second-order logic, equality
                  and disequality constraints}
}