Analysis of information sources in references of the Wikipedia article "Mellophone" in English language version.
Courtois came out with an instrument that bore the name of a virtuoso cornetist and instrument builder named Herman Koenig, this instrument being called the Koenig horn. Koenig's role is uncertain - he was a very good instrument builder in his own right, but it is also possible that the instruments were built by Courtois at a suggestion or request by Koenig, or the two men may have worked together on the instrument
