The MPAA Film Rating History by JamesMoulton1988 on DeviantArt

List of NC-17 rated films - Wikipedia

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The first American film to receive an X rating

Was there ever a genuine meaning to the X, XX and XXX ratings on

Is 'X-Rated: The Greatest Adult Movies of All Time' on Netflix in Australia? Where to Watch the Documentary - New On Netflix Australia & New Zealand

Bad Manners X Review, Bad Manners Twitter Review Ratings, Bad Manners Kannada Movie X Review

X Factor 2014 ratings: Return of Cheryl Cole and Simon Cowell attracts biggest debut since 2011, The Independent

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Fire-Rated Type X Gypsum Board