  General expressions of the electron yield in (^{57})Fe integral conversion
electron M\"ossbauer spectroscopy were derived depending on the angle of
incidence of the (\gamma)-rays, on the source polarization and on the isotopic
abundance of the source and the absober (blackness effects) using an
exponential escape function of the electrons originating from all
M\"ossbauer-resonance-related processes. The present approach provides a firm
theoretical basis to determine the alignment and direction of magnetization in
the absorber. The intensity formulae were justified by least squares fits of
(\alpha-^{57})Fe spectral intensities measured in linearly and elliptically
polarized source and absorber geometries. The fits reproduce the experimentally
set angles with high accuracy. Limits of the current approach and its relation
to other, less complete treatments in the literature are discussed.
