Bb+2. Bartolozzi, Bruno. New Sounds for Woodwind. London: Oxford University Press, 1971, p. 31.

 x x x | x x o Ab
    w
Bb

Bb+2. Reinhard, Johnny. "The Microtonal Bassoon." The Double Reed 10/2 (Fall 1987): 42.

x x x | x x o F Ab
   w   Bb

Bb+2. Vigder, Scott. "A Table of Quarter-Tone Fingerings for the Bassoon," TheDouble Reed 4/2 (October 1981): 44. These fingerings were extracted from Sergio Penazzi'sMetodo per Fagotto (Edizoni Suvini Zerboni-Milano, 1971).

x  x  x  | x x o Ab
          Bb
Bb B(C D?)

Fingerings for microtones