@Article{dln:link-prediction,
  author =	 {David Liben-Nowell and Jon Kleinberg},
  title =	 {The Link-Prediction Problem for Social Networks},
  journal =	 {Journal of the American Society for Information
                  Science and Technology},
  year =	 2007,
  month =	 may,
  volume =	 58,
  number =	 7,
  pages =	 {1019--1031}
}