/usr/lib/ is in libtext-bibtex-perl 0.71-1build1.
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/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/perl5/
/usr/lib/x86_64-linux-gnu/perl5/5.22/
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/usr/lib/x86_64-linux-gnu/perl5/5.22/auto/Text/BibTeX/BibTeX.so