“…The case of Banach algebras has been considered in [16], [4] and [5]. In this paper starting from a result of [5] we complete our previous result in [10] and also strengthen it to include the corresponding results of [4], [5] (cf. In this paper starting from a result of [5] we complete our previous result in [10] and also strengthen it to include the corresponding results of [4], [5] (cf.…”