Physics for
scientists and engineers: a strategical approach/Randall
D. Knight 3rd ed.
ISBN 978-0-321-74090-8
http://www.acs.psu.edu/thermoacoustics/refrigeration/faqs.htm
http://www.coolsound.us/work.html
https://www.fas.org/sgp/othergov/doe/lanl/pubs/00326024.pdf