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@Book{            Bachmann,
  Author        = "Bachmann, Jorg P.",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:27 +0200",
  Title         = "Characterization of Petri net Languages",
  Year          = "2011",
  File          = "Characterization of Petri net Languages - Bachmann (0) (0) - a - a.pdf"
}

@Book{ Bachmann, Author = "Bachmann, Jorg P.", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:27 +0200", Title = "Characterization of Petri net Languages", Year = "2011", File = "Characterization of Petri net Languages - Bachmann (0) (0) - a - a.pdf" }