Abstract. We show that each jointly quasinormal family of operators acting on a separable Hilbert space generates a reflexive algebra with property ${\msbm A}_1(1)$.

AMS Subject Classification (1991): 47D25, 47B20

Keyword(s): Reflexive operator algebra, quasinormal operator

Received June 2, 1994. (Registered under 5704/2009.)