Yes and no. GNU refers to the system as a whole, while GNU/Hurd is more
specific, saying that it is the GNU system running on the Hurd -- to
differentiate it from the GNU system running on Linux, GNU/Linux.
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any later version published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
is included in the section entitled GNU Free Documentation