@article{DesharnaisMoellerStruth2004,
  author    = {Jules Desharnais and Bernhard M{\"o}ller and Georg Struth},
  title     = {Modal Kleene algebra and applications - a survey},
  journal   = {Journal on Relational Methods in Computer Science},
  volume    = {1},
  pages     = {93 -- 131},
  url       = {http://www.cosc.brocku.ca/Faculty/Winter/JoRMiCS/Vol1/PDF/v1n5.pdf},
  year      = {2004},
}