From the Bassoon-Family Fingering Companion by Terry B. Ewell - Cooper, L. Hugh. "Bassoon Clinic Series, Part Four," Etude: the Music Magazine 47/6 (June 1949): 356. Corey, Gerald E. "How to Improve Your Tuning on the Bassoon." The Journal of the International Double Reed Society 8 (1980): 33. Moritz, Frederick. "A Dissertation on the Use of Alternate Fingerings for Some of the High Register Notes on the Heckel and Heckel-Type Bassoons." The Double Reed 8/3 (Winter 1985): 28, 29, 32. Wilson, George H. "Bassoon Intonation: No Mystery!" The Instrumentalist 18/7 (February 1964): 66. Reprinted in Woodwind Anthology (Evanston: The Instrumentalist Company, 1976), p. 589.