Zamenhof Day (but not the international English one), bore a special version of their logo (a Doodle) emblazoned with the Esperanto flag in honor of the occasion, which generated, on the 30 biggest Wikipedia languages, 1,750,000 page views on the articles "L. L. Zamenhof". Zamenhof Day Zamenhof Day (), also called Esperanto Book Day, is celebrated on 15 December, the birthday of Esperanto creator L. L. Zamenhof. It is the most widely celebrated day in Esperanto culture. On this day, Esperantists hold information sessions and cultural gatherings to promote literature in Esperanto. The history of celebrating Esperanto on Zamenhof's birthday can be
Ludwik Krzywicki in the organization and management of scientific bodies. He served as vice-director of the Central Statistical Office, taught at the University of Warsaw (1919–36) and other institutions of higher education, and directed the Socio-Economic Institute. During World War II he was injured during the defence of Warsaw in September 1939, and the bomb that destroyed his apartment also caused the loss of most of his papers and manuscripts. His working conditions worsened and he died of heart disease in 1941. Ludwik Krzywicki Ludwik Krzywicki (21 August 1859 – 10 June 1941) was a Polish anthropologist, economist and sociologist. One of