  We derive expressions for the total and linearly-polarized synchrotron
emissivity of an element of plasma containing relativistic particles and
disordered magnetic field which has been sheared or compressed along three
independent directions. Our treatment follows that given by Matthews & Scheuer
(1990) in the special case of a power-law electron energy spectrum. We show
that the emissivity integrals depend on a single parameter, making it
straightforward to generate one-dimensional look-up tables. We also demonstrate
that our formulae give identical results to those in the literature in special
cases.
