Homological methods in group theory, Generators, relations, and presentations of groups, Free products of groups, free products with amalgamation, Higman-Neumann-Neumann extensions, and generalizations, infinite one-relator group with torsion, Resolutions; derived functors (category-theoretic aspects), Homological dimension (category-theoretic aspects), conjugacy classes of finite subgroups, Article, Cancellation theory of groups; application of van Kampen diagrams, quasi-projektive resolution, permutation module, aspherical groups, 510.mathematics, periodic Tate-cohomology, Fundamental groups and their automorphisms (group-theoretic aspects), graph of groups, finite quasi-projective dimension