1. Ion Recombination Control in Atmosphere for Human Comfort;Beckett,1951
2. W. Wesley Hicks, U. S. Pat. 2,576,399, Nov. 27, 1951; 2,589,613, Mar. 18, 1952; 2,639,972, May 26, 1953; Ion Controllers.
3. The Measurement of Electrostatic Potential Due to Net Ion Space Charge in Air;Carroll;AIEE Trans.,1955
4. Control of Air Ion Density in Rooms;Skilling;Jour. Franklin Inst.,1953