# References for non-vacuum dispersion relations

Hi guys,

I'm looking for some references where dispersion relations, say for photons, are explicitely written out in a generic medium. In other words, the dispersion relation for particles not propagating in the vacuum is a different one than the standard vacuum one $$E^2 = p^2 + m^2$$ and I'm looking for papers/books where such relations are written out. Possibly for the photon or for electrons. Do you know any?