  The free energy, non-gradient terms of the Ginzburg-Landau expansion, and the
jump of the specific heat of a multiband anisotropic-gap clean BCS
superconductor are derived in the framework of a separable-kernel
approximation. Results for a two-band superconductor, d-wave superconductor,
and some recent models for MgB_2 are derived as special cases.
