Coba jelasin Sumber dari Charles Messier dalam bahasa melayu dong

O'Meara, Stephen James (1998). Deep Sky Companions: The Messier Objects. Cambridge University Press.

Charles Messier Biography at Students for the Exploration and Development of Space. Accessed July 2007

Short biography of Charles Messier and history of the Messier Object Catalog  by Jon Zander at OurDarkSkies.com . Accessed July 2007

Life of a Comet Hunter: Messier and Astrobiology Professor Mark Brake and Martin Griffiths, Astrobiology Magazine European Edition, Spring 2007. Accessed July 2007