@inproceedings{Oliveira*2008:Visitor,
  title = "The Visitor Pattern as a Reusable, Generic, Type-Safe Component",
  author = "Bruno C. d. S. Oliveira and Meng Wang and Jeremy Gibbons",
  year = "2008",
  booktitle = "Object-Oriented Programming: Systems, Languages, Applications (OOPSLA)",
  url = "http://www.comlab.ox.ac.uk/jeremy.gibbons/publications/visitor.pdf",
}