Nightingale, T.R.T., and R.E. Halliwell. “In-Situ Sound Insulation Measurement When a Room Is Very Absorptive”. Canadian Acoustics 29, no. 3 (September 1, 2001): 60–61. Accessed September 21, 2024. https://jcaa.caa-aca.ca/index.php/jcaa/article/view/1383.