@Unpublished{     lean2019,
  Author        = "Avigad, Jeremy and de Moura, Leonardo and Kong, Soonho",
  date-added    = "2019-03-20 21:11:06 +0100",
  date-modified = "2019-12-31 10:57:50 +0100",
  Keywords      = "lean theorem prover",
  Title         = "Theorem Proving in Lean",
  Year          = "2019",
  File          = "theorem\_proving\_in\_lean (0) (0) - a - a - b.pdf",
  file-2        = "theorem\_proving\_in\_lean - a - a - a - b.pdf"
}

@Unpublished{ lean2019, Author = "Avigad, Jeremy and de Moura, Leonardo and Kong, Soonho", date-added = "2019-03-20 21:11:06 +0100", date-modified = "2019-12-31 10:57:50 +0100", Keywords = "lean theorem prover", Title = "Theorem Proving in Lean", Year = "2019", File = "theorem_proving_in_lean (0) (0) - a - a - b.pdf", file-2 = "theorem_proving_in_lean - a - a - a - b.pdf" }