Analysis of information sources in references of the Wikipedia article "Single-wavelength anomalous diffraction" in English language version.
MAD: [...] The differences in anomalous scattering around the edge allow calculation of phase angles without the phase ambiguity present in SAD experiments, although density modification will usually still be necessary to obtain an easily interpretable map. [...] Although very powerful, MAD phasing has declined somewhat in popularity relative to SAD because of the more limited choice of heavy atoms, the difficulty of avoiding radiation damage, and the requirement for a synchrotron beamline. [...] SAD: [...] SAD is often performed with selenomethionine-incorporated protein, but any anomalously scattering atom (including sulfur, if the data are of very high quality) may be used.