“…It is well-known that L 1 (G) is always closed under the convolution. Saeki [22] proved that, for 1 < p < ∞, the space L p (G) is closed under the convolution if and only if G is compact; see also Burnham [4], Crombez [6]- [7], Duggal [8], Gaudet [10], Johnson [12], Kunze [13], Lohoue [14], Milnes [15], Rajagopalan [16]- [19], Rickert [20]- [21], Urbanik [23], Zelazko [24]- [27] for some special cases, Kinani and Benazzouz [9] and also Abtahi, Nasr Isfahani and Rejali [2]- [3] for the more general case of weighted L p -spaces.…”