“…The literature on singular problems for equations of the form = − has primarily focused on local operators as the Laplacian, = − div ∇ (see [2,4,7,10,17,18,21]), or the -Laplacian, = − div ( |∇ | −2 ∇ ) , > 1 (see [1,9,[13][14][15]20]). As for singular problems involving nonlocal (fractional) operators, the literature is quite recent and more restricted to = ( −Δ ) (see [3,8]). In general, the energy functional associated with a singular problem of the form = − is not differentiable.…”