@incollection{Weyer2002,
  author = "Mark Weyer",
  title = "Decidability of {S1S} and {S2S}",
  booktitle = "Automata, Logics, and Infinite Games: A Guide to Current Research",
  publisher = "Springer",
  year = 2002,
  editor = "Erich Gr{\"a}del and Wolfgang Thomas and Thomas Wilke",
  number = "2500",
  series = "Lecture Notes in Computer Science",
  chapter = "12",
  pages = "207--230"
}