@inproceedings{ShYi01,
  author = "Nikolay Shilove and Kwangkeun Yi",
  title = "On Expressive and Model Checking Power of Propositional Program Logics",
  booktitle = "Perspectives of System Informatics: 4th International Andrei Ershov Memorial Conference",
  volume = "2244",
  series = "Lecture Notes in Computer Science",
  pages = "39-46",
  year = "2001"
}