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@Book{            BethBook,
  Author        = "Puppis, G.",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:27 +0200",
  Keywords      = "MSO",
  Note          = "Available at \url{http://www.dimi.uniud.it/\textasciitilde puppis/BethBook.pdf}",
  Title         = "Automata for Branching and Layered Temporal Structures",
  Year          = "2009",
  File          = "Automata for Branching and Layered Temporal Structures - Puppis (0) (1) - a - a.pdf",
  file-2        = "Automata for Branching and Layered Temporal Structures - Puppis (1) (0) - a - a.pdf"
}

@Book{ BethBook, Author = "Puppis, G.", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:27 +0200", Keywords = "MSO", Note = "Available at \url{http://www.dimi.uniud.it/\textasciitilde puppis/BethBook.pdf}", Title = "Automata for Branching and Layered Temporal Structures", Year = "2009", File = "Automata for Branching and Layered Temporal Structures - Puppis (0) (1) - a - a.pdf", file-2 = "Automata for Branching and Layered Temporal Structures - Puppis (1) (0) - a - a.pdf" }