Second-order analysis of a boundary control problem for the viscous   Cahn--Hilliard equation with dynamic boundary condition
  In this paper we establish second-order sufficient optimality conditions for a boundary control problem that has been introduced and studied by three of the authors in the preprint arXiv:1407.3916. This control problem regards the viscous Cahn--Hilliard equation with possibly singular potentials and dynamic boundary conditions. 
Pierluigi Colli, M. Hassan Farshbaf-Shaker, Gianni Gilardi, J\"urgen   Sprekels
math.AP