MPAA X18 Rated Logo by JamesMoulton1988 on DeviantArt

MPAA Rating Bumper Rated X Remake (1970-1971) by TheAnthonyCorp on DeviantArt

X (2022) - IMDb

cinema history - Why would a movie that appears pornographic via it's rating (X) receive an Academy Award? - Movies & TV Stack Exchange

A History of the X and NC-17 Ratings – The Hollywood Reporter

File:X MPAA.png - Wikipedia

IPX Waterproof Rating Guide – Hypergear US

File:MPAA X RATING (block).svg - Wikipedia

X-Men: Days Of Future Past Includes Nudity According To MPAA Rating

X-Files IMDB Rankings : r/XFiles

X (BBFC), Rating System Wiki