1. 1) Q. Zhang and X. Su, "High-speed optical measurement for the drumhead vibration," Opt. Express, 13, 3110–3116 (2005).
2. 2) R. Worland, "Normal modes of a musical drumhead under non-uniform tention," J. Acoust. Soc. Am., 127, 525–533 (2010).
3. 3) R. Hashimoto, K. Yatabe and Y. Oikawa, "Visualizing mode shape of a drumhead under non-uniform tension for estimating tuning condition using Fourier transform profilometry," Proc. 24th Int. Congr. Acoust., 8 pages (2022).
4. 4) N. H. Fletcher and T. D. Rossing, "Circular membranes," in The Physics of Musical Instruments, 2nd ed. (Springer-Verlag, New York, 1998), Chap. 3, Sect. 3, pp. 73–75.
5. 5) X. Su and W. Chen, "Fourier transform profilometry: A review," Opt. Lasers Eng., 35, 263–284 (2001).