L. L. Zamenhof L. L. Zamenhof Ludwik Lejzer Zamenhof (; , ; – ), credited as L. L. Zamenhof and sometimes as the pseudonymous Dr. Esperanto, was a Polish-Jewish ophthalmologist and the creator of Esperanto, the most successful constructed language in the world. He grew up fascinated by the idea of a world without war and believed that this could happen with the help of a new international auxiliary language, which he first developed in 1873 while still in school. Zamenhof was born on 15 December (3 December OS) 1859, the son of Markus Zamenhof (27 January 1837 - 29 November 1907) and
Ludwik Kalkstein October 1994, in Munich, Germany. Ludwik Kalkstein Ludwik "Hanka" Kalkstein, also known as Ludwik Kalkstein-Stoliński, (13 March 1920, Warsaw – 26 October 1994, Munich); was one of the better known German Gestapo agents during the Warsaw Uprising as well as a Stalinist informant following the Soviet takeover of Poland. Along with his wife (Blanka Kaczorowska "Sroka"), they became traitors to the Armia Krajowa under not just one but two consecutive totalitarian regimes. Kalkstein was responsible for the arrest and execution by the Nazis of at least fourteen Polish underground officers, including the General Stefan Rowecki. Arrested by the Gestapo in