E4-F4. Ewell, Terry B. (28 April 1995)
tr o x |(x) x x
E4-F4. Timm, Everett LeRoy. The Woodwinds; Performance and Instructional Techniques. Boston: Allyn and Bacon, 1964, p. 175.
Eb x o x | x x tr
Heckel-System (German) Bassoon Trills and Shakes by Note Names