Ensminger, Dale (2009). Ultrasonics: data, equations, and their practical uses, Volume 10. Boca Raton, Florida: CRC Press (Taylor & Francis Group). pp. 324-333. ISBN978-0-8247-5830-1.
Williams, Douglas (1994). Guide to Cleaner Technologies: Cleaning and Degreasing Process Changes. Washington DC: United States Environmental Protection Agency. pp.18-20.
Ultrasonic Cleaning, Tool and Manufacturing Engineers Handbook, Vol. 3, Materials, Finishing, and Coating, C. Wick and R.F.Veilleux, Ed., Society of Manufacturing Engineers, 1985.
Montreal Protocol on Substances that Deplete the Ozone Layer Regulatory Summary and Montreal Protocol on Substances that Deplete the Ozone Layer Questions and Answers, Environmental Protection Agency