Columbia subject headings:
Science fiction films--History and criticism.
X-Men films--History and criticism.
Harvard subject headings:
Politics in motion pictures--Congresses.
Power (Social sciences) in motion pictures--Congresses.
X-Men (Fictitious characters)--Congresses.
X-Men (Motion picture)--Congresses.
Princeton subject headings:
Science fiction films--History and criticism.
X-Men films--History and criticism.