/usr/ is in libinhomog-dev 0.1.7.1-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/libinhomog.a
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/include/
/usr/include/inhomog/
/usr/include/inhomog/alloc_big_array.h
/usr/include/inhomog/biscale_partition.h
/usr/include/inhomog/config.h
/usr/include/inhomog/inhomog.h
/usr/include/inhomog/parse_noempty_strtox.h
/usr/include/inhomog/power_spectrum_flatspace.h
/usr/lib/x86_64-linux-gnu/pkgconfig/inhomog.pc
/usr/share/
/usr/share/doc/
/usr/share/doc/libinhomog-dev/
/usr/share/doc/libinhomog-dev/copyright
/usr/share/doc/libinhomog-dev/examples/
/usr/share/doc/libinhomog-dev/examples/README
/usr/share/doc/libinhomog-dev/examples/inhomog_demo.c.gz
/usr/lib/x86_64-linux-gnu/libinhomog.so
/usr/share/doc/libinhomog-dev/AUTHORS
/usr/share/doc/libinhomog-dev/NEWS.gz
/usr/share/doc/libinhomog-dev/README
/usr/share/doc/libinhomog-dev/TODO
/usr/share/doc/libinhomog-dev/changelog.Debian.gz