“…The same problem happens in the investigation of existence and approximation results for convolution equations. This line of investigation was initiated by Malgrange [39] and developed by several authors (see, for instance [14,15,16,22,23,24,25,26,27,33,34,40,41,42,43,45,46,50]). In this context, a result of [26] (refined in [5]) gives a general method to prove existence and approximation results for convolution equations defined on certain spaces of entire functions of bounded type.…”