  Multiple reflection of X-rays may be important when an accretion disc and its
hot corona have a complicated geometry, or if returning radiation due to
gravitational light bending is important, or in emission from a funnel such as
proposed in some gamma-ray burst models. We simulate the effects of multiple
reflection by modifying the boundary condition for an X-ray illuminated slab.
Multiple reflection makes the soft X-ray spectrum steeper (softer) and
strengthens broad emission and absorption features, especially the K-shell
features of iron. This may be important in explaining the spectra of sources
such as the Narrow-Line Seyfert 1 galaxy 1H0707-495.
