Before revision: URL English summary of the Danish Ph.D. dissertation, The Arc Transmitter - a Comparative Study of the Invention, Development and Innovation of the Poulsen System in Denmark, England and the United States, by Hans Buhl, 1995 URL URL - From the electric arc of Petrov to the radio broadcast of speech
After revision: .URL English summary of the Danish Ph.D. dissertation, The Arc Transmitter - a Comparative Study of the Invention, Development and Innovation of the Poulsen System in Denmark, England and the United States, by Hans Buhl, 1995 URL URL - From the electric arc of Petrov to the radio broadcast of speech