For years, this has been the intermediate study book for flute. Book 1 contains a wealth of famous studies by such composers as Andersen, Gariboldi, Kohler, and Terschak. Book 2 is a continuation of Book 1, including etudes by Kummer. For further technical and musical development, Book 3 features the work of Boehm, Kronke, Kohler, and Mollerup.