“…Here we remark that for the continuous focusing NLS equation iq t = q xx + |q| 2 q where |q| 2 = qq * , its double Wronskian solution was given in [11] in 1983, while for the discrete NLS equation (3), although there were many discussions on its solutions [12][13][14], surprisingly, it seems there is no explicit double Casoratian form that was presented as its solutions. Besides, (18) does not provide a solution with nonzero background for equation (3) with δ = 1, i.e.…”