V
[VS85] Moshe Y. Vardi and Larry J. Stockmeyer. Improved Upper and Lower Bounds for Modal Logics of Programs. In STOC'85, pages 240-251. ACM Press, May 1985. 
@inproceedings{stoc1985-VS,
  author =              {Vardi, Moshe Y. and Stockmeyer, Larry J.},
  title =               {Improved Upper and Lower Bounds for Modal Logics of
                         Programs},
  booktitle =           {{P}roceedings of the 17th {A}nnual {ACM} {S}ymposium
                         on the {T}heory of {C}omputing ({STOC}'85)},
  acronym =             {{STOC}'85},
  publisher =           {ACM Press},
  pages =               {240-251},
  year =                {1985},
  month =               may,
}
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