/usr/share/acl2-4.3/books/centaur/aig/ is in acl2-books-source 4.3-3.
This file is owned by root:root, with mode 0o755.
..
/usr/share/acl2-4.3/books/centaur/aig/aig-equivs.lisp
/usr/share/acl2-4.3/books/centaur/aig/aig-vars.lisp
/usr/share/acl2-4.3/books/centaur/aig/base.lisp
/usr/share/acl2-4.3/books/centaur/aig/bddify-correct.lisp
/usr/share/acl2-4.3/books/centaur/aig/bddify.lisp
/usr/share/acl2-4.3/books/centaur/aig/cert.acl2
/usr/share/acl2-4.3/books/centaur/aig/eval-restrict.lisp
/usr/share/acl2-4.3/books/centaur/aig/faig-op-commutativity.lisp
/usr/share/acl2-4.3/books/centaur/aig/g-aig-eval.acl2
/usr/share/acl2-4.3/books/centaur/aig/g-aig-eval.lisp
/usr/share/acl2-4.3/books/centaur/aig/induction.lisp
/usr/share/acl2-4.3/books/centaur/aig/misc.lisp
/usr/share/acl2-4.3/books/centaur/aig/portcullis.acl2
/usr/share/acl2-4.3/books/centaur/aig/portcullis.lisp
/usr/share/acl2-4.3/books/centaur/aig/three-four.lisp
/usr/share/acl2-4.3/books/centaur/aig/witness.acl2
/usr/share/acl2-4.3/books/centaur/aig/witness.lisp