We continue the program initiated in a previous work, of applying
integro-differential methods to Neumann Homogenization problems. We target the
case of linear periodic equations with a singular drift, which includes (with
some regularity assumptions) divergence equations with \emph{non-co-normal}
oscillatory Neumann conditions. Our analysis focuses on an induced
integro-differential homogenization problem on the boundary of the domain.
Also, we use homogenization results for regular Dirichlet problems to build
barriers for the oscillatory Neumann problem with the singular gradient term.
We note that our method allows to recast some existing results for fully
nonlinear Neumann homogenization into this same framework. This version is the
journal version.Comment: This is the revised version that appeared in SIM