I am following advice from this page:
and I'm particularly puzzled by the following topics (in bold):
Maxwell's laws in a medium. Boundaries. Solving the equations in:
* vacumm and homogeneous medium (electromagnetic waves)
* in a box (wave guides)
* at boundaries (fraction and reflection)
The vector potential and gauge invariance (extremely important)
emission and absorption on EM waves (antenna)
light scattering against objects.
What books deal with those subjects?