Zubritsky, Elizabeth; Cook, Jia-Rui (10 November 2010). "Cassini Sees Saturn on a Cosmic Dimmer Switch". NASA / California Institute of Technology / Jet Propulsion Laboratory. Archived from the original on 21 November 2010. Retrieved 2 January 2011.
Zubritsky, Elizabeth; Cook, Jia-Rui (10 November 2010). "Cassini Sees Saturn on a Cosmic Dimmer Switch". NASA / California Institute of Technology / Jet Propulsion Laboratory. Archived from the original on 21 November 2010. Retrieved 2 January 2011.