User's Manual

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versions of the General Public License from time to time. Such
new versions will be similar in spirit to the present version, but
may dier in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the
Program species a version number of this License which
applies to it and “any later version”, you have the option of
following the terms and conditions either of that version or of
any later version published by the Free Software Foundation. If
the Program does not specify a version number of this License,
you may choose any version ever published by the Free
Software Foundation.
10. If you wish to incorporate parts of the Program into other free
programs whose distribution conditions are dierent, write to
the author to ask for permission.
For software which is copyrighted by the Free Software
Foundation, write to the Free Software Foundation; we
sometimesmakeexceptionsforthis.Ourdecisionwillbe
guided by the two goals of preserving the free status of all
derivatives of our free software and of promoting the sharing
and reuse of software generally.