@Article{BaaGT-IC-06,
  author =	 {Franz Baader and Silvio Ghilardi and Cesare Tinelli},
  title =	 {A new combination procedure for the word problem
                  that generalizes fusion decidability results in
                  modal logics},
 journal =	 {Information and Computation},
 year =	 2006,
  volume =       {204},
  number =       {10},
  pages      =   {1413--1452},
}