12 books • 1 series
Book #4: Flexibility with Triplets and Glissando N-4 Bass Trombone
Book #5: Flexibility with Triplets and Glissando N-5 Bass Trombone
Book #6: Flexibility with Triplets and Glissando Bass N-6 Trombone
Book #7: Flexibility with Triplets and Glissando N-7 Bass Trombone
Book #9: Flexibility with Triplets and Glissando N-9 Bass Trombone