1. F Major -- 2. Bb Major -- 3. Eb Major -- 4. Ab Major -- 5. Db Major -- 6. Gb Major -- 7. B Major -- 8. E Major -- 9. A Major -- 10. D Major -- 11. G Major -- 12. C Major.
Title from resource description page (viewed March 10, 2020). Written in 2007. "Coordination studies in 12 keys for 4-part trombone ensemble." For trombone quartet.