Gillock's 24 Lyric Preludes in Romantic Style is a wonderful collection of miniature pieces that range from late beginner to late intermediate levels. Inspired by Chopin's preludes, this set also features pieces in all 24 major and minor keys. The Humming Bird is an excellent study in fast and light notes on the right hand. Gillock is careful to avoid the thumb from going under the other fingers at any point, making this piece much more accessible for intermediate pianists.