Eggen, O. J.; Lynden-Bell, D.; Sandage, A. R. (November 1962). "Evidence from the motions of old stars that the Galaxy collapsed". Astrophysical Journal. 136: 748–766. Bibcode:1962ApJ...136..748E. doi:10.1086/147433.
Sandage, A.R. (March 1961). "The Ability of the 200-inch Telescope to Discriminate Between Selected World Models". Astrophysical Journal. 133 (2): 355–392. Bibcode:1961ApJ...133..355S. doi:10.1086/147041.
Eggen, O. J.; Lynden-Bell, D.; Sandage, A. R. (November 1962). "Evidence from the motions of old stars that the Galaxy collapsed". Astrophysical Journal. 136: 748–766. Bibcode:1962ApJ...136..748E. doi:10.1086/147433.
Sandage, A. (April 1990). "On the formation and age of the Galaxy". Journal of the Royal Astronomical Society of Canada. 84: 70–88. Bibcode:1990JRASC..84...70S. ISSN0035-872X.
Sandage, A.R. (March 1961). "The Ability of the 200-inch Telescope to Discriminate Between Selected World Models". Astrophysical Journal. 133 (2): 355–392. Bibcode:1961ApJ...133..355S. doi:10.1086/147041.
Sandage, A. (April 1990). "On the formation and age of the Galaxy". Journal of the Royal Astronomical Society of Canada. 84: 70–88. Bibcode:1990JRASC..84...70S. ISSN0035-872X.