Instability of solitary wave solutions for the generalized BO–ZK equation

In this paper we study the generalized BO–ZK equation in two space dimensionsut+upux+αHuxx+εuxyy=0.ut+upux+αHuxx+εuxyy=0. We review the existence theory for solitary waves and prove that they are nonlinearly unstable if p   belongs to the range 4/3