/usr/share/doc/texlive-doc/latex/ntgclass/ is in texlive-latex-recommended-doc 2009-15.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/texlive-doc/latex/ntgclass/00readme.txt
/usr/share/doc/texlive-doc/latex/ntgclass/a4.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/artdoc.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/artdoc.tex.gz
/usr/share/doc/texlive-doc/latex/ntgclass/brief.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/brief.tex.gz
/usr/share/doc/texlive-doc/latex/ntgclass/briefdoc.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/briefdoc.tex.gz
/usr/share/doc/texlive-doc/latex/ntgclass/catalog.txt
/usr/share/doc/texlive-doc/latex/ntgclass/changes.txt
/usr/share/doc/texlive-doc/latex/ntgclass/classdoc.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/classdoc.tex.gz
/usr/share/doc/texlive-doc/latex/ntgclass/manifest.txt
/usr/share/doc/texlive-doc/latex/ntgclass/ntgclass.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/rapdoc.pdf
/usr/share/doc/texlive-doc/latex/ntgclass/rapdoc.tex.gz