Nikola Tesla British Patent 2801 - Improvements in Reciprocating Engines and Means for Regulating the Period of the Same
Nikola Tesla British Patent 2812 - Improvements in Methods of and Apparatus for the Generation of Electric Currents of Defined Period
Nikola Tesla U.S. Patent 568,178 - Method of Regulating Apparatus for Producing Electric Currents of High Frequency
Nikola Tesla U.S. Patent 568,176 - Apparatus for Producing Electrical Currents of High Frequency and Potential
Nikola Tesla German Patent 87269 - Device for Generating Electrical Currents with a Constant Number of Vibrations