/usr/share/doc/irstlm/changelog.Debian.gz is in irstlm 6.00.05-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/irstlm/../libirstlm1/changelog.Debian.gz
/usr/share/doc/irstlm/../libirstlm1/changelog.Debian.gz