1. Berberian, S. K. (1972).Baer *-Rings, Springer, Berlin.
2. Bourbaki, N. (1953/1955).Espaces vectoriels topologiques (éléments de mathématiques, Livre V), 2 vols., Hermann, Paris.
3. Dixmier, J. (1981).Von Neumann Algebras, North-Holland, Amsterdam.
4. Dunford, N., and Schwartz, J. T. (1958/1963/1971).Linear Operators, 3 vols., Interscience, New York.
5. Effros, E. G. (1965).Pacific Journal of Mathematics,15, 1153?1164.