  We calculate the energy of the magnetostatic interaction between two
ferromagnetic films with uniform magnetization and correlated interfaces (the
"orange-peel" effect). The "orange-peel" coupling is anisotropic: the
interaction is ferromagnetic when the films are magnetized in-plane; and it is
antiferromagnetic when magnetization is out-of-plane. The interaction
anisotropy can be used to distinguish the "orange-peel" effect from the
interlayer exchange coupling.
