The fractional Hartree equation without the Ambrosetti-Rabinowitz   condition
  We consider a class of pseudo-relativistic Hartree equations in presence of general nonlinearities not satisfying the Ambrosetti-Rabinowitz condition. Using variational methods based on critical point theory, we show the existence of two non trivial signed solutions, one positive and one negative. 
Mauro Francesconi, Dimitri Mugnai
math.AP