Sadržaji su preuzeti sa:

Rubin, Vera C. "Galaxy." Microsoft® Encarta® 2006 [DVD]. Redmond, WA: Microsoft Corporation, 2005.
Microsoft ® Encarta ® 2006. © 1993-2005 Microsoft Corporation. All rights reserved.
 

Više informacija na:

http://www.phy.syr.edu/courses/CCD_NEW/seti/topics/cosmology/galaxy.html

http://hou.lbl.gov/ISE/new/galaxy/index.html

http://www.astro.princeton.edu/~frei/galaxy_catalog.html