Generalized Snell's law and Fresnel equations

Goal: find the reflectivity of an electromagnetic wave incident on an interface between two absorbing media (or, if that proves too challenging, on an interface between an absorbing and a non-absorbing medium with the wave originating in the absorbing medium)

To accomplish this goal, first a generalized Snell’s law for an interface between two absorbing media must be found to relate the incident angle with the transmission angle. Then, the reflection coefficients must be found to determine the reflectivity.