“…3. Smith (1974Smith ( , 1975, Christensen and Lo (1979), Hashin and Rosen (1964) and Hashin (1962Hashin ( , 1963Hashin ( , 1968Hashin ( , 1990Hashin ( , 1991a eventually improved on the CSA model. The CSA assumes that the particles are spherical and, moreover, that the action on the particle is transmitted through a spherical interphase shell.…”