@inproceedings{O'Loughlin:20096+,
  author = "O'Loughlin, Martin",
  title = "{Penrose Limits, Singularities and DLCQ}",
  doi = "10.22323/1.075.0023",
  booktitle = "Proceedings of Black Holes in General Relativity and String Theory {\textemdash} PoS(BHs, GR and Strings)",
  year = 2009,
  volume = "075",
  pages = "023"
}