Jean van Heijenoort’s Contributions to Proof Theory and Its History.Irving H. Anellis -2012 -Logica Universalis 6 (3):411-458.detailsJean van Heijenoort was best known for his editorial work in the history of mathematical logic. I survey his contributions to model-theoretic proof theory, and in particular to the falsifiability tree method. This work of van Heijenoort’s is not widely known, and much of it remains unpublished. A complete list of van Heijenoort’s unpublished writings on tableaux methods and related work in proof theory is appended.