/usr/share/doc/libcitygml0-dev/changelog.Debian.gz is in libcitygml0-dev 0.14+svn128-1+3p0p1+4.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libcitygml0-dev/../libcitygml0/changelog.Debian.gz