@article{wang2014k,
  title={k-Zero day safety: A network security metric for measuring the risk of unknown vulnerabilities},
  author={Wang, Lingyu and Jajodia, Sushil and Singhal, Anoop and Cheng, Pengsu and Noel, Steven},
  journal={IEEE Transactions on Dependable and Secure Computing},
  volume={11},
  number={1},
  pages={30--44},
  year={2014},
  paperurl={http://dx.doi.org/10.1109/TDSC.2013.24},
  publisher={IEEE}
}