1. Homotopy Type Theory in Agda, an Agda library of formalized proofs, available at \url{https://github.com/HoTT/HoTT-Agda}.
2. Lean theorem prover, a proof assistant together with a library of formalized proofs, available at \url{https://github.com/leanprover/lean}.
3. RedPRL, a proof assistant for Computational Cubical Type Theory together with a library of formalized proofs, available at \url{http://www.redprl.org/}.
4. The HoTT Library, a Coq library of formalized proofs, available at \url{https://github.com/HoTT/HoTT}.
5. Univalent categories and the Rezk completion;Ahrens, Benedikt;Math. Structures Comput. Sci.,2015