  The aim of this paper is to study a class of nonlocal fractional Laplacian
equations depending on two real parameters. More precisely, by using an
appropriate analytical context on fractional Sobolev spaces due to Servadei and
Valdinoci, we establish the existence of three weak solutions for nonlocal
fractional problems exploiting an abstract critical point result for smooth
functionals. We emphasize that the dependence of the underlying equation from
one of the real parameter is not necessarily of affine type.
