1. Diffraction theory;Bouwkamp;Repts. on Prog. in Phys.,1954
2. On the transmission of sound through small apertures;Ingerslev;Ingeniorvidenskabeliga Skrifter,1944
3. Dynamical Theory of Sound;Lamb,1931
4. Theory of Sound;Rayleigh,1877
5. Theory of Sound;Rayleigh,1877