/usr/include/GNUstep/Frameworks/PopplerKit.framework/Headers is in libpopplerkit-dev 0.0.20051227svn-7.1build17.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/include/GNUstep/Frameworks/PopplerKit.framework/Versions/1.0