Eugenio Coșeriu
Eugenio Coșeriu (, ; 27 July 1921 – 7 September 2002) was a linguist who specialized in Romance languages at the University of Tübingen, author of over 50 books, honorary member of the Romanian Academy.In 1970 he coined the terms diatopic, diastratic and diaphasic to describe linguistic variation. Provided by Wikipedia