@article{GuttmannMoeller2018,
  author    = {Walter Guttmann and Bernhard M{\"o}ller},
  title     = {Normal design algebra},
  journal   = {The Journal of Logic and Algebraic Programming},
  volume    = {79},
  number    = {2},
  pages     = {144 -- 173},
  doi       = {10.1016/j.jlap.2009.07.002},
  year      = {2018},
}