1. III. On the mathematical theory of sound
2. B. Riemann,Göttingen Abhandlungen, 1860, reprinted inCollected Works(Dover Publications, New York, 1953), p. 156.
3. An alternative way of writing Eq. (3) is p = p0+Aρ−ρ0ρ0+B2ρ−ρ0ρ02. (3a) Up to terms of second order in ρ−ρ0, this equation is identical with Eq. (3), with P−Q = p0, A = γP = ρ0c02, B = Pγ(γ−1) = (γ−1)ρ0c02.
4. H. Lamb,Dynamical Theory of Sound(E. Arnold, London, 1925), 2nd ed., p. 177, ff.