  In this article, we present the general form of the full electromagnetic
Green function which is suitable for the application in bulk materials physics.
In particular, we show how the seven adjustable parameter functions of the free
Green function translate into seven corresponding parameter functions of the
full Green function. Furthermore, for both the fundamental response tensor and
the electromagnetic Green function, we discuss the reduction of the Dyson
equation on the four-dimensional Minkowski space to an equivalent,
three-dimensional Cartesian Dyson equation.
