“…It has been shown, indeed, that the singularities of this type provide a behavior of the solutions which resembles the situation encountered while dealing with superlinear systems (see, e.g. [1,2,3,6,7,8,9,10,11,12,13]). In the same spirit, the existence of subharmonic solutions can also be easily obtained, but we will avoid such a discussion, for briefness.…”