L. L. Zamenhof his honour. In 1959, Unesco honoured Zamenhof in the occasion of his centenary. In 2015 Unesco decided to support the celebration of the 100th anniversary of the death of Ludwik Zamenhof. Zamenhof was 12 times nominated for the Nobel Peace Prize. His birthday, 15 December, is celebrated annually as Zamenhof Day by users of Esperanto. On 15 December 2009, Esperanto's green-starred flag flew on the Google search web page, in a commemorative Google Doodle to mark Zamenhof's 150th birthday. The house of the Zamenhof family, dedicated to Ludwik Zamenhof, and the Białystok Esperanto Centre, are sites of the Jewish Heritage
Ludwik Birkenmajer w przekładzie polskim" (1920) · Mikołaj Kopernik, "O obrotach ciał niebieskich i inne pisma" (2004) · Andrzej Śródka, "Uczeni polscy XIX-XX stulecia". Warszawa 1994, vol. I, p. 155-157 . Paweł Tarasiewicz, Zbigniew Pańpuch, "Birkenmajer Ludwik Antoni", "Powszechna encyklopedia filozofii" vol. I, Lublin 2000 · Władysław Horbacki, "Ludwik Antoni Birkenmajer (1855-1929)". Łódź 1930 Ludwik Birkenmajer Ludwik Antoni Birkenmajer (18 May 1855 - 20 November 1929), Polish historian of science, physicist, astronomer, professor of the Jagiellonian University. Descended from the German family settled in Galicia (Southern Poland) during the time of the Napoleon wars, later a part of the Austrian Habsburg Empire.