“Lua 5.1 Reference Manual.” The Programming Language Lua. 24 Feb. 2010. 17 Nov. 2010.
http://www.lua.org/manual/5.1/
This site is a complete formal documentation of the language.
“lua-users wiki: For Tutorial.” lua-users.org. 17 Nov. 2010. http://lua-users.org/wiki/ForTutorial.
This site thoroughly explains the loops available in Lua.
Wikipedia contributors. "Lua (programming language)." Wikipedia, The Free Encyclopedia. 6 Nov. 2010.
Web. 17 Nov. 2010 http://en.wikipedia.org/wiki/Lua_(programming_language).
This site offers a good overview of the historical background of Lua.