https://m4lvin.github.io/lean4-pdl/docs/
(Run make dependencies.svg to update this.)
- https://malv.in/2020/borzechowski-pdl - the German original proof by Borzechowski (1988) and the English translation (2020)
- https://github.com/m4lvin/tablean - previous project for Basic Modal Logic, in Lean 3. Code from there has been ported to Lean 4 and is included here in the
Bmlfolder. - https://w4eg.de/malvin/illc/tapdleau - tableaux prover implemented in Haskell, useful to run examples.