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Copyright (C) 2012
Standards Of Fundamental Astronomy Board
of the International Astronomical Union.

SOFA Software License



1. The Software is owned by the IAU SOFA Board ("SOFA").

2. Permission is granted to anyone to use the SOFA software for any
   purpose, including commercial applications, free of charge and
   without payment of royalties, subject to the conditions and
   restrictions listed below.

3. You (the user) may copy and distribute SOFA source code to others,
   and use and adapt its code and algorithms in your own software,
   on a world-wide, royalty-free basis.  That portion of your
   distribution that does not consist of intact and unchanged copies
   of SOFA source code files is a "derived work" that must comply
   with the following requirements:

   a) Your work shall be marked or carry a statement that it
      (i) uses routines and computations derived by you from
      software provided by SOFA under license to you; and
      (ii) does not itself constitute software provided by and/or
      endorsed by SOFA.

   b) The source code of your derived work must contain descriptions
      of how the derived work is based upon, contains and/or differs
      from the original SOFA software.

   c) The names of all routines in your derived work shall not
      include the prefix "iau" or "sofa" or trivial modifications
      thereof such as changes of case.

   d) The origin of the SOFA components of your derived work must
      not be misrepresented;  you must not claim that you wrote the
      original software, nor file a patent application for SOFA
      software or algorithms embedded in the SOFA software.

   e) These requirements must be reproduced intact in any source
      distribution and shall apply to anyone to whom you have
      granted a further right to modify the source code of your
      derived work.

   Note that, as originally distributed, the SOFA software is
   intended to be a definitive implementation of the IAU standards,
   and consequently third-party modifications are discouraged.  All
   variations, no matter how minor, must be explicitly marked as
   such, as explained above.

4. You shall not cause the SOFA software to be brought into
   disrepute, either by misuse, or use for inappropriate tasks, or
   by inappropriate modification.

5. The SOFA software is provided "as is" and SOFA makes no warranty
   as to its use or performance.   SOFA does not and cannot warrant
   the performance or results which the user may obtain by using the
   SOFA software.  SOFA makes no warranties, express or implied, as
   to non-infringement of third party rights, merchantability, or
   fitness for any particular purpose.  In no event will SOFA be
   liable to the user for any consequential, incidental, or special
   damages, including any lost profits or lost savings, even if a
   SOFA representative has been advised of such damages, or for any
   claim by any third party.

6. The provision of any version of the SOFA software under the terms
   and conditions specified herein does not imply that future
   versions will also be made available under the same terms and

In any published work or commercial product which uses the SOFA
software directly, acknowledgement (see is

Correspondence concerning SOFA software should be addressed as

    By email:
    By post:   IAU SOFA Center
               HM Nautical Almanac Office
               UK Hydrographic Office
               Admiralty Way, Taunton
               Somerset, TA1 2DN
               United Kingdom
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