1. Introduction to the theory of linear non-selfadjoint operators in Hilbertspace;Gochberg,1965
2. An introduction to harmonic analysis;Katznelson,1968
3. Über Strukturbedingungen für Fourierreihen;Leindler;Math. Zeitsch.,1965
4. Normed rings;Naimark,1964
5. Classical harmonic analysis and locally compact groups;Reiter,1968