A random field formulation of Hookes law in all elasticity classes

For each of the $8$ isotropy classes of elastic materials, we consider a homogeneous random field taking values in the fixed point set $mathsf{V}$ of the corresponding class, that is isotropic with respect to the natural orthogonal representation of a group lying between the isotropy group of the class and its normaliser. We find the general form of the correlation tensors of orders $1$ and $2$ of such a field, and the fields spectral expansion.