Proceedings of the Steklov Institute of Mathematics, volume 196, issue four of four, 1992. Translated from the Russian. Papers discuss the variations of positive quadratic forms, partitioning of Euclidean space into L-polytopes of some perfect lattices, Spanier-Whitehead duality and the stability of the intersection of compacta, curvatures of tangent spheres, geodesic on a Seifert-Weber manifold, three-dimensional spherical forms, the dissociation of point system, and homology on presheaves of sets. No index. Annotation copyright Book News, Inc. Portland, Or.