Invited Talks.- Applying Formal Methods in the Large.- Automating Theorem Proving with SMT.- Certifying Voting Protocols.- Invited Tutorials.-Counterexample Generation Meets Interactive Theorem Proving: Current Results and Future Opportunities.- Canonical Structures for the Working Coq User.- Regular Papers.- MaSh: Machine Learning for Sledgehammer.- Scalable LCF-Style Proof Translation.- Lightweight Proof by Reflection Using a Posteriori Simulation of Effectful Computation.- Automatic Data Refinement.- Data Refinement in Isabelle/HOL.- Light-Weight Containers for Isabelle: Efficient, Extensible, Nestable.- Ordinals in HOL: Transfinite Arithmetic up to (and Beyond) ω1.- Mechanising Turing Machines and Computability Theory in Isabelle/HOL.-A Machine-Checked Proof of the Odd Order Theorem.- Kleene Algebra with Tests and Coq Tools for while Programs.-Program Analysis and Verification Based on Kleene Algebra in Isabelle/HOL.- Pragmatic Quotient Types in Coq.- Mechanical Verification of SAT Refutations with Extended Resolution.- Formalizing Bounded Increase.- Formal Program Optimization in Nuprl Using Computational Equivalence and Partial Types.- Type Classes and Filters for Mathematical Analysis in Isabelle/HOL.- Formal Reasoning about Classified Markov Chains in HOL.- Practical Probability: Applying pGCL to Lattice Scheduling.- Adjustable References.- Handcrafted Inversions Made Operational on Operational Semantics.- Circular Coinduction in Coq Using Bisimulation-Up-To Techniques.- Program Extraction from Nested Definitions.- Subformula Linking as an Interaction Method.- Automatically Generated Infrastructure for De Bruijn Syntaxes.- Shared-Memory Multiprocessing for Interactive Theorem Proving.- A Parallelized Theorem Prover for a Logic with Parallel Execution.- Rough Diamonds.- Communicating Formal Proofs: The Case of Flyspeck.- Square Root and Division Elimination in PVS.- The Picard Algorithm for Ordinary Differential Equations in Coq.- Stateless Higher-Order Logic with Quantified Types.- Implementing Hash-Consed Structures in Coq.- Towards Certifying Network Calculus.- Steps towards Verified Implementations of HOL Light.