  We obtain an approximate global stationary and axisymmetric solution of
Einstein's equations which can be thought as a simple two layers star model: a
self-gravitating ball built up by two layers of perfect fluid having different
linear equation of state moving in a rigid motion pattern. Using the
post-Min\-kows\-kian formalism (weak-field approximation) and considering
rotation as a perturbation (slow-rotation approximation), we find approximate
interior and exterior (asymptotically flat) solutions to this problem in
harmonic coordinates. Interior and exterior solutions are matched, in the sense
described by Lichnerowicz, on the surfaces of constant pressure, to obtain a
global solution.
