@inproceedings{heunenjacobs:arrows,
  title = "Arrows, like Monads, are Monoids",
  author = "Chris Heunen and Bart Jacobs",
  year = "2006",
  journal = "MFPS, Electronic Notes in Theoretical Computer Science",
  pages = "219-236",
  volume = "158",
  doi = "10.1016/j.entcs.2006.04.012",
}