@article{DBLP:journals/logcom/DitmarschRV08,
  author    = {Hans P. van Ditmarsch and
               Ji Ruan and
               Rineke Verbrugge},
  title     = {Sum and Product in Dynamic Epistemic Logic},
  journal   = {J. Log. Comput.},
  volume    = {18},
  number    = {4},
  year      = {2008},
  pages     = {563-588},
  ee        = {http://dx.doi.org/10.1093/logcom/exm081},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}