“Dueling Fundamentals for Two Trumpets” was published by Mountain Peak Music. The UNT College of Music assistant professor of trumpet says, "The book challenges and engages two trumpeters when practicing fundamentals in a duet format. The book includes exercises dealing with sound production, flexibility, articulation, finger dexterity, and range." The book also places value on collaborative practice.
https://www.mountainpeakmusic.com/dueling-fundamentals-for-two-trumpets/