Terhardt, E. (1989). On the role of ambiguity of perceived pitch in music. In: Proc. 13th Intern. Congr. Acoust., Belgrad (3), 35-38
With reference to results of psychophysical research on pitch perception, the following notions are established and discussed: (1) With regard to musical sounds, ambiguity of pitch is an ordinary phenomenon that differs only gradually from one sound to the other. (2) Ambiguity of pitch is confined to a finite set of alternatives. (3) Ambiguity of pitch creates perceptual similarity of sound objects. (4) Similarity in turn is a basic organisational principle of music.