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 Maciej Ludwik Maciej Ludwik Maciej (May 16, 1915 – March 12, 2007) was a Polish military pilot, who participated in World War II. Son of Jan and Anna (née Donocik), Ludwik Maciej graduated from Primary School in his hometown of Dziedzice and continued his education in a Grammar School in Bielsko (presently Nicolas Copernicus High School in Bielsko-Biała). During his school years he played football for 'Grażyna', which was part of the 'Sokół' ("Falcon") Polish Gymnastic Society. Having voluntarily joined the military forces in 1935, he took his military oath and after becoming a qualified pilot, he joined the 2nd Air