diff --git a/COPYING.txt b/COPYING.txt
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+     This software has been authored by an employee or employees of Los
+     Alamos National Security, LLC, operator of the Los Alamos National
+     Laboratory (LANL) under Contract No. DE-AC52-06NA25396 with the
+     U.S.  Department of Energy.  The U.S. Government has rights to use,
+     reproduce, and distribute this software.  The public may copy,
+     distribute, prepare derivative works and publicly display this
+     software without charge, provided that this Notice and any
+     statement of authorship are reproduced on all copies.  Neither the
+     Government nor LANS makes any warranty, express or implied, or
+     assumes any liability or responsibility for the use of this
+     software.  If software is modified to produce derivative works,
+     such modified software should be clearly marked, so as not to
+     confuse it with the version available from LANL.