@article{Wucknitz:2009xu,
  author = "Wucknitz, Olaf",
  title = "{The gravitational lens J1131-1231 --- How to miss an opportunity and how to avoid it }",
  doi = "10.22323/1.072.0102",
  journal = "PoS",
  year = 2009,
  volume = "IX EVN Symposium",
  pages = "102"
}