@article{Ait-Kaci89,
  author	= {A\"\it-Kaci, Hassan and Boyer, Robert and Lincoln, Patrick and Nasr, Roger},
  year		= {1989},
  title		= {Efficient Implementation of Lattice Operations},
  journal	= {ACM Transactions on Programming Languages and Systems},
  volume	= {11},
  number	= {1},
  pages		= {115--146}
}