Steven Mauk, professor of music (saxophone), was one of the contributing authors in The Vandoren Etude and Exercise Book for Saxophone: The Secrets of Ten Master Saxophonists. This pedagogical publication features chapters by international saxophone authors/performers. Mauk's submission is entitled Preliminary Altissimo Exercises and instructs saxophonists on how to play the notes above the normal range of the saxophone. This is only the most recent of his pedagogical publications, which now number over 100 books and articles.
https://www.ithaca.edu/intercom/article.php/20111207110703522