/usr/share/acl2-6.3/books/paco/ is in acl2-books-source 6.3-5.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-6.3/books/paco/database.acl2
/usr/share/acl2-6.3/books/paco/database.lisp
/usr/share/acl2-6.3/books/paco/elim-dest.acl2
/usr/share/acl2-6.3/books/paco/elim-dest.lisp
/usr/share/acl2-6.3/books/paco/foundations.acl2
/usr/share/acl2-6.3/books/paco/foundations.lisp
/usr/share/acl2-6.3/books/paco/induct.acl2
/usr/share/acl2-6.3/books/paco/induct.lisp
/usr/share/acl2-6.3/books/paco/output-module.acl2
/usr/share/acl2-6.3/books/paco/output-module.lisp
/usr/share/acl2-6.3/books/paco/paco.acl2
/usr/share/acl2-6.3/books/paco/paco.lisp
/usr/share/acl2-6.3/books/paco/prove.acl2
/usr/share/acl2-6.3/books/paco/prove.lisp
/usr/share/acl2-6.3/books/paco/rewrite.acl2
/usr/share/acl2-6.3/books/paco/rewrite.lisp
/usr/share/acl2-6.3/books/paco/simplify.acl2
/usr/share/acl2-6.3/books/paco/simplify.lisp
/usr/share/acl2-6.3/books/paco/type-set.acl2
/usr/share/acl2-6.3/books/paco/type-set.lisp
/usr/share/acl2-6.3/books/paco/utilities.acl2
/usr/share/acl2-6.3/books/paco/utilities.lisp