Columbia subject headings:
Castles--France--Plouézoc'h--History.
Coast defenses--France--Plouézoc'h--History.
Prisons--France--Plouézoc'h--History.
Harvard subject headings:
Castles--France--Plouézoc'h--History.
Coast defenses--France--Plouézoc'h--History.
Prisons--France--Plouézoc'h--History.
Princeton subject headings:
Castles--France--Plouézoc'h--History.
Coast defenses--France--Plouézoc'h--History.
Prisons--France--Plouézoc'h--History.