/usr/share/man/man3/glCompressedTextureSubImage2D.3G.gz is in opengl-4-man-doc 1.0~svn31251-1build1.
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It is a symlink to /usr/share/man/man3/glCompressedTexSubImage2D.3G.gz
/usr/share/man/man3/glCompressedTexSubImage2D.3G.gz