/usr/share/xml/entities/xhtml/xhtml-lat1.ent is in w3c-dtd-xhtml 1.1-5ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/xml/entities/xhtml/../../xhtml/schema/dtd/1.0/xhtml-lat1.ent
/usr/share/xml/entities/xhtml/../../xhtml/schema/dtd/1.0/xhtml-lat1.ent