R. Ierusalimschy\, L. H. de Figueiredo\, W. Celes\, "The Evolution of an Extension Language: A History of Lua"\, Proceedings of V Brazilian Symposium on Programming Languages (2001) B-14--B-28.

Languages mentioned

• DEL {1991} Data Entry Language
• LUA {1993} Language extension language
• SOL {1992} Simple Object Language