I have clear proofs!
 Official song title: The official title of the song is リンガ・フランカ ! Only this Japanese title exists! Proof are the official tracklist by the label Universal Music Japan  and the official press release of the entertainment company SM.
 Common title use in Wikipedia: It is common to use the official song titles in a Wikipedia article, example: 첫 눈 by the group EXO (Chinese release: 初雪), only the original song titles are used. Parentheses (round brackets) inform about meanings and/or translations!
 Translations: Translations of song titles should be real translations! Official dictionaries should be used to get correct translations. In the case of リンガ・フランカ the official English translation is "lingua franca".
 Specialty of "lingua franca": It's a loan word which is usually only used by people with advanced language skills!
 Correct title editing: リンガ・フランカ (Romanization: Ringa Furanka, English: Lingua Franca)
 Concerning the alleged iTunes spelling: If iTunes does have the song listed as "linguafranc", it's an embarrassing misspelling! Only correct language spelling should be used in Wikipedia!
 Wikipedia admins: This is what I will send to the Wikipedia admins to prove my point and in case I will still be harassed with false accusations.