Before revision:  We apply these maximum principles to obtain uniqueness and a priori maximum principle estimates for classical solutions to boundary value and obstacle problems defined by these degenerate-elliptic operators , again in the presence of a second-order boundary condition, for Dirichlet or Neumann boundary conditions along the complement of the degeneracy locus.
After revision:  We apply these maximum principles to obtain uniqueness and a priori maximum principle estimates for smooth solutions to boundary value and obstacle problems defined by these degenerate-elliptic operators , again in the presence of a second-order boundary condition, for Dirichlet or Neumann boundary conditions along the complement of the degeneracy locus.