D.11. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised
versions of the GNU Free Documentation License from time to
time. Such new versions will be similar in spirit to the
present version, but may differ in detail to address new
problems or concerns. See
https://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing
version number. If the Document specifies that a particular
numbered version of this License "or any later version"
applies to it, you have the option of following the terms and
conditions either of that specified version or of any later
version that has been published (not as a draft) by the Free
Software Foundation. If the Document does not specify a
version number of this License, you may choose any version
ever published (not as a draft) by the Free Software
Foundation.