.. _wcslib: https://www.atnf.csiro.au/people/mcalabre/WCS/wcslib/index.html
.. _distortion paper: https://www.atnf.csiro.au/people/mcalabre/WCS/dcs_20040422.pdf
.. _SIP: https://irsa.ipac.caltech.edu/data/SPITZER/docs/files/spitzer/shupeADASS.pdf
.. _ds9: http://ds9.si.edu/
.. _FITS WCS standard: https://fits.gsfc.nasa.gov/fits_wcs.html
.. _paper_I: https://arxiv.org/pdf/astro-ph/0207407.pdf
.. _paper_II: https://arxiv.org/pdf/astro-ph/0207413.pdf
.. _paper_III: https://arxiv.org/pdf/astro-ph/0507293.pdf
.. _paper_IV: https://arxiv.org/pdf/1409.7583.pdf
