Interlinguistics of interlinguistics are, however, not so constructive, but rather descriptive, comparative, historic, sociolinguistic, or concerned with translation by humans or machines. As for Esperanto, which is the most widely used constructed interlanguage, there is a relatively abundant literature about the language itself and its philology (see Esperantology). Only a few of the many constructed languages have been applied practically to any noteworthy extent. The most prosperous were Volapük (1879, Johann Martin Schleyer), Esperanto (1887 Ludwik Lejzer Zamenhof), Latino sine flexione (1903, Giuseppe Peano), Ido (1907, Louis Couturat), Occidental-Interlingue (1922, Edgar de Wahl) and Interlingua (1951, IALA and Alexander Gode), with
Ludwik Leibler Ludwik Leibler Ludwik Leibler, born in 1952 is a Polish physicist. He is Professor of École supérieure de physique et de chimie industrielles de la ville de Paris (ESPCI ParisTech) and member of the National Academy of Engineering. Ludwik Leibler received his PhD in 1976 in Theoretical Physics from Warsaw University, and then spent two years as a post-doctoral fellow at the Collège de France in Paris under the direction of Pierre-Gilles de Gennes. He is a researcher in Centre National de Recherche Scientifique (CNRS) which he joined first in Stasbourg then in Paris where he worked on theoretical and