For an author who writes in two or more languages, the rule includes an "in case of doubt" provision, when there is no predominant language, that sends the cataloger to reference sources of the person’s country of residence or activity. If there are no such reference sources, the person is not listed, or for any other reason reference sources do not settle the matter, use in the heading the form of name in the person’s native language.

After an author has been established, if subsequently received works show a form in a language not selected for the heading, change the heading when 80% of the author’s works are in that language.

See also:

22.3B. Language