/usr/share/doc/libxml-libxml-perl/examples/test.dtd is in libxml-libxml-perl 1.89+dfsg-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 | <!ELEMENT article (pubData* , pubArticleID* , pubDate+ , pubName+ , section+ , memo* , headline1* , headline2* , byline* , lead* , rest* , graphics* , keywords* , caption*)>
<!ELEMENT pubData (#PCDATA)>
<!ELEMENT pubArticleID (#PCDATA)>
<!ELEMENT pubDate (#PCDATA)>
<!ELEMENT pubName (#PCDATA)>
<!ELEMENT section (#PCDATA)>
<!ELEMENT memo (#PCDATA)>
<!ELEMENT headline1 (#PCDATA)>
<!ELEMENT headline2 (#PCDATA)>
<!ELEMENT byline (#PCDATA)>
<!ELEMENT lead (#PCDATA)>
<!ELEMENT rest (#PCDATA)>
<!ELEMENT graphics (#PCDATA)>
<!ELEMENT keywords (#PCDATA)>
<!ELEMENT caption (#PCDATA)>
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