This advanced text explores the theory of groups and their matrix representations. The main focus rests upon point and space groups, with applications to electronic and vibrational states. 1969 edition.

Maria I. Petrashen (1906-77) taught and conducted research at Leningrad State University. This text, which she co-wrote with E. D. Trifonov, is the result of their successful application of group-theoretical methods to the investigation of the electronic structure of solids.