On the geometry in codimension 2 of Grassmann manifolds -- Invarianten binรคrer formen -- Deformation kompakter komplexer Rรคume -- Kurven auf den Hilbertschen Modulflรคchen und Klassenzahlrelationen -- Picard schemes of formal schemes; application to rings with discrete divisor class group -- Modifications of complex varieties and the Chow Lemma -- Some results on cubic threefolds -- Studies on degeneration -- Hyperelliptic curves over number fields -- Modulrรคume algebraischer Mannigfaltigkeiten -- Abbildungen in arithmetische Quotienten hermitesch symmetrischer Rรคume -- Singular abelian surfaces and binary quadratic forms -- to classification theory of algebraic varieties and compact complex spaces