  Electromagnetic wave propagation inside isotropic material media
characterized by dielectric coefficients $\varepsilon_{\mu\nu}(E,B)$ and
$\mu_{\mu\nu}(E,B)$ is examined. The regime of the eikonal approximation is
considered. The Hadamard method of field disturbances is used and the
dispersion relations are obtained by solving the Fresnel equation. Some
applications of the formalism are presented. Particularly, birefringence
phenomena induced by applied external fields are derived and discussed. It is
shown that magnetoelectric birefringence effect can occur even without the
presence of Kerr and Cotton-Mouton effects, provided the physical system
satisfies certain conditions.
