@article{article97c81f63,
title   = {A multiplicity result via Ljusternick-Schnirelmann category and Morse theory for a fractional Schrödinger equation in RN},
author = {Figueiredo, Giovany Malcher and Siciliano, Gaetano},
year = {2016},
doi = {10.1007/s00030-016-0355-4},
journal   = {Nonlinear Differential Equations and Applications}
}