... These include support for spectral coordinate systems, and compliance with FITS WCS papers I, II and III. ... Supported . ... Supported (all coordinate systems [including helio-ecliptic] and algorithm codes listed in papers I, II and III, with the exception of the ``STOKES'' and ``COMPLEX'' values defined in paper I, the ``CUBEFACE'' value defined in paper II, and the ``-TAB'' algorithm defined in paper III) . ... Supported (all systems, except ecliptic coordinates are currently assumed to be FK5) ....