Zamenhof-Esperanto object of 1044 Zamenhof-Esperanto objects in 54 countries") and until his death in 2001 he listed a total of 1260 such objects. It is he who coined the acronym "ZEO". Currently, Robert Kamiński of Poland is the person charged with the registration of ZEOs by the Universal Esperanto Association. The highest number of ZEOs per country is situated in Brazil. In Poland, the birthplace of Esperanto, there are more than a hundred of them. Zamenhof-Esperanto object A Zamenhof-Esperanto object (, ZEO) is a monument or a place linked to L. L. Zamenhof, the constructed language Esperanto he created and first published
Ludwik Birkenmajer of scholars. He was married Zofia (Sophie), the daughter of Franciszek Karliński, the professor of astronomy in the Jagiellonian University, and inherited his library embracing mostly the books on mathematics and physics. They had three sons: Aleksander Ludwik (historian of culture and exact sciences, and bibliologist), Józef (poet, interpreter and literature historian), and Wincenty (Polish philologist, teacher and renown Tatra Mountains-climber). His grandson is Krzysztof Birkenmajer (professor of geology, member of the Polish Academy of Sciences). In 2011 the Institute for the History of Science of the Polish Academy of Sciences received the name of father and son: Ludwik &