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@Book{            pettorossi,
  Author        = "Pettorossi, Alberto",
  date-added    = "2021-09-07 12:24:59 +0200",
  date-modified = "2021-09-07 12:25:26 +0200",
  Title         = "Elements of Computability, Decidability, and Complexity",
  Year          = "2009",
  File          = "Elements of Computability, Decidability, and Complexity - ComputabilityDecidabilityComplexity.pdf"
}

@Book{ pettorossi, Author = "Pettorossi, Alberto", date-added = "2021-09-07 12:24:59 +0200", date-modified = "2021-09-07 12:25:26 +0200", Title = "Elements of Computability, Decidability, and Complexity", Year = "2009", File = "Elements of Computability, Decidability, and Complexity - ComputabilityDecidabilityComplexity.pdf" }