  Theoretical formalisms for the homogenization of particulate composites are
identified as following either the direct scattering approach (DSA) or the
indirect scattering approach (ISA). Both approaches can take inclusion
size-dependence and distribution statistics into account. However, the DSA is
generally limited to mediums with direction-independent constitutive properties
and inclusions with simple shapes, but the ISA is not hobbled thus.
