@article{HoefnerMoeller2006,
  author    = {Peter H{\"o}fner and Bernhard M{\"o}ller},
  title     = {Towards an algebra of hybrid systems},
  journal   = {Lecture Notes in Computer Science},
  volume    = {3929},
  pages     = {121 -- 133},
  doi       = {10.1007/11734673_10},
  year      = {2006},
}