Web Links

http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/cfr/1998/47cfr15.pdf. This document contains electromagnetic emissions limits for the 13.553MHz to 13.567MHz "free" band (page 50), as well as other bands.

Dielectric Phenomena in High Voltage Engineering, by F.W. Peek, 1929.
http://plasmatechnics.com. This company offers high-voltage devices intended for electrostatic generation, corona discharge ozone generators, and other high-votage applications that may require a variety of specifications.
.

http://sundial.sundial.net/~rogerr/ionovac.htm by Roger Russel, 1996-2000. This site contains a detailed history of the Iovovac Ion tweeter with pictures of the original Ionovacs. There is a section where the author discusses an article he wrote in 1961 describing sound fidelity testing he performed on an actual Ionovac tweeter. There is a list of usedful article references from early hi-fi magazines at the bottom of his page.

http://members.aol.com/uhaumann2/plasma/ion.htm . This site is a do-it-yourself plasma tweeter by Ulrich Haumann contains schematics, contruction tips and instructions. There is also a plasma tweeter gallery at the site.
http://www.ee.vill.edu/~cdanjo/plasma.html. Site by Colin Joye, 1999, describes his building of a pair of plasma tweeters along with troublshooting tips, schematics, parts lists and contruction descriptions.
http://www.ee.vill.edu/~cdanjo/plasma2.html. Another site by Colin Joye, 2001, describing his second pair of plasma tweeters which are similar to the first.

http://www.misty.com/people/don/tesla.html. This site, by Don Klipstein, 1998, contains documentation of his Tesla coil experiments as well as a mathematical explanation for why the high-frequency high-voltage Tesla coils do not cause shocks to people, but may cause burns. He tested his hypothesis by running high-voltage through himself at various frequencies and concluded that frequencies above 20kHz are not felt, even with a wet hand.
.

http://www.audioasylum.com/audio/general/messages/14476.html. This is a discussion regarding Doppler distortion and what it is. The author is describing possible problems associated with a device that undoes doppler distortion due to a microphone. His assertions that the device would undo natural doppler distortions (as they occur in a piano frame or in air, for example) and therefore cause an increase in distortion are incorrect as they apply to said device since the device is intended to only undo those doppler frequency shifts associated with the microphone and other sensor equipment only. Doppler distortion is still a very real problem in dynamic cone spakers.
http://www.magnan.com/column.shtml. This page gives a short description of Doppler distortion and how to help alleviate it in the case of a light-weight speaker cabinet that vibrates back and forth due to the equal and opposite reaction law as the speaker pushes its cone forward and backward.
http://utenlt.el.utwente.nl/links/schurer/hans.html. This site is the Ph.D thesis of Hans Schurer on compensating for nonlinear effects in speakers using DSP. He gives a list of books related to Loudspeaker distortion, from which there may be a few that address the topic of Doppler distorion or sub-harmonic distortion.

http://www.cco.caltech.edu/~boyk/spectra/spectra.htm. This site is a study of the freqency content of several common musical instruments that have a lot of sound above the 20kHz limit of the human ear.
http://www.atcsd.com/HTML/newwhitepaper.html. This site explains a HyperSonic sound transducer that creates a pseudo-point source by beaming ultrasonic sound waves off of a wall and making use of intermodulation to create audible sound.