[1] Hawking, S. (1988) A Brief History of Time, the Expanding Universe. Bantam Press, UK, 42.
[2] Speed of Gravity, The Speed of Gravitational Waves in the General Theory of Relativity Is Equal to the Speed of Light in Vacuum.
http://en.wikipedia.org/wiki/Speed_of_gravity
[3] Cosmic Microwave Background Radiation.
http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation
[4] Hawking, S. (1988) A Brief History of Time from Big Bang to Black Holes—The Expanding Universe. Bantam Press, UK, 41.
[5] Lifting the Veil on Hubble’s Constant Ten + 1 Measurements of the Hubble Constant.
http://science.nasa.gov/science-news/science-at-nasa/1999/ast25may99_2/
[6] Parsec Megaparsecs and Gigaparsecs.
http://en.wikipedia.org/wiki/Parsec
[7] Gravitational Time Dilation.
http://genesismission.4t.com/Physics/gtd.htm