Level-Confluence of 3-CTRSs in Isabelle/HOL
  We present an Isabelle/HOL formalization of an earlier result by Suzuki, Middeldorp, and Ida; namely that a certain class of conditional rewrite systems is level-confluent. Our formalization is basically along the lines of the original proof, from which we deviate mostly in the level of detail as well as concerning some basic definitions. 
Christian Sternagel and Thomas Sternagel
cs.LO