@inproceedings{backes07causality,
  author       = {Backes, Michael and Cortesi, Agostino and Maffei, Matteo},
  title        = {Causality-based Abstraction of Multiplicity in Security Protocols},
  booktitle    = {Proceedings of 20th IEEE Computer Security Foundation Symposium (CSF)},
  month        = {June},
  year         = {2007}
}