“…On the other hand, there is a class of type-I C ¤ -algebras called dual, which have often appeared recently (see, for example, [2,3,6]), although it has been a long time since the notion of a dual C ¤ -algebra was rst introduced by Kaplansky [5] (see also [4, 4.7.20]). Recall that a C ¤ -algebra A is said to be dual if the sum of the minimal left ideals of A is dense in A, or, equivalently, A is isomorphic to a C ¤ -subalgebra of the C ¤ -algebra of all compact operators on some Hilbert space.…”