1. Blades, J. (1970). “Percussion Instruments and Their History,” Faber and Faber, London. p. 97.
2. Fletcher, N.H. (1985). Nonlinear frequency shifts in quasi-spherical cap shells: Pitch glide in Chinese gongs. J. Acoust. Soc. Am. 78, 2069–2073.
3. Hampton, D.S., Alexis, C., and Rossing, T.D. (1987). Note coupling in Caribbean steel drums. Paper GG3, Acoustical Soc. Am., Miami.
4. Holland, J. (1978). “Percussion,” Schirmer, New York. p. 60.
5. Leung, K.K., and Rossing, T.D. (1988). Sound spectra of Caribbean steel drums. Paper AE1, American Physical Society, Crystal City, Virginia.