InhaltsangabeSession 1: Invited Talk.- SAT-Based Counterexample Guided Abstraction Refinement in Model Checking.- Session 2.- Equational Abstractions.- Deciding Inductive Validity of Equations.- Automating the Dependency Pair Method.- An AC-Compatible Knuth-Bendix Order.- Session 3.- The Complexity of Finite Model Reasoning in Description Logics.- Optimizing a BDD-Based Modal Solver.- A Translation of Looping Alternating Automata into Description Logics.- Session 4.- Foundational Certified Code in a Metalogical Framework.- Proving Pointer Programs in Higher-Order Logic.- ?.- Subset Types and Partial Functions.- Session 5.- Reasoning about Quantifiers by Matching in the E-graph.- Session 6.- A Randomized Satisfiability Procedure for Arithmetic and Uninterpreted Function Symbols.- Superposition Modulo a Shostak Theory.- Canonization for Disjoint Unions of Theories.- Matching in a Class of Combined Non-disjoint Theories.- Session 7.- Reasoning about Iteration in Gödel's Class Theory.- Algorithms for Ordinal Arithmetic.- Certifying Solutions to Permutation Group Problems.- Session 8: System Descriptions.- TRP++ 2.0: A Temporal Resolution Prover.- IsaPlanner: A Prototype Proof Planner in Isabelle.- 'Living Book':- 'Deduction', 'Slicing', 'Interaction'.- The Homer System.- Session 9: CASC-19 Results.- The CADE-19 ATP System Competition.- Session 10: Invited Talk.- Proof Search and Proof Check for Equational and Inductive Theorems.- Session 11: System Descriptions.- The New WALDMEISTER Loop at Work.- About VeriFun.- How to Prove Inductive Theorems? QuodLibet!.- Session 12: Invited Talk.- Reasoning about Qualitative Representations of Space and Time.- Session 13.- Superposition with Equivalence Reasoning and Delayed Clause Normal Form Transformation.- The Model Evolution Calculus.- Translation of Resolution Proofs into Short First-Order Proofs without Choice Axioms.- Efficient Instance Retrieval with Standard and Relational Path Indexing.- Session 14.- Monodic Temporal Resolution.- A Principle for Incorporating Axioms into the First-Order Translation of Modal Formulae.- Schematic Saturation for Decision and Unification Problems.- Session 15.- Unification Modulo ACUI Plus Homomorphisms/Distributivity.- Source-Tracking Unification.- Optimizing Higher-Order Pattern Unification.- Decidability of Arity-Bounded Higher-Order Matching.