@misc{Ko-pcOrn-categorical,
  title = "Categorical organisation of the ornament–refinement framework",
  author = "Hsiang-Shang Ko and Jeremy Gibbons",
  year = "2013",
  howpublished = "Submitted to POPL'14",
  month = "July",
  url = "http://www.cs.ox.ac.uk/people/hsiang-shang.ko/pcOrn-categorical/pcOrn-categorical.pdf",
}