Hans-Jürgen Bürckert Alexander Herold Deepak Kapur Jörg H. Siekmann Mark E. Stickel Michael Tepp Hantao Zhang Opening the AC-Unification Race. 465-474 1988 4 J. Autom. Reasoning 4 db/journals/jar/jar4.html#BurckertHKSSTZ88 http://dx.doi.org/10.1007/BF00297251