“…In [10], the current authors and Skoug showed that for all F and G in E σ , F α,β (F X) and ((F * G) α X) exist and belong to E σ for all nonzero complex numbers α and β and the condition by X(x) = x(T ) while δF (y|w) exists and belongs to E σ for all y and w in K. For related work see [2,7,9,11,15] and for a detailed survey of previous work see [14].…”