Goudenhooft's "Apercu du Trombone Basse Double Noix, volume 2" (published French title) is a continuation of volume 1, with 24 etudes (numbered 43 through 67). These etudes are somewhat more advanced and all are for solo bass trombone (no duet accompaniment as in volume 1). The author suggests they are designed for the player to develop a perfect syncronization between the tongue, valve(s) and slide. -cdp