CFITSIO (See: https://heasarc.gsfc.nasa.gov/fitsio/)

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the United States), U.S. Government as represented by the Administrator
of the National Aeronautics and Space Administration.  No copyright is
claimed in the United States under Title 17, U.S. Code.
Permission to freely use, copy, modify, and distribute this software
and its documentation without fee is hereby granted, provided that this
copyright notice and disclaimer of warranty appears in all copies.
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THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND,
EITHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO,
ANY WARRANTY THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE, AND FREEDOM FROM INFRINGEMENT, AND ANY WARRANTY THAT THE
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