Eisenhauer, F.; Schdel, R.; Genzel, R.; Ott, T.; Tecza, M.; Abuter, R.; Eckart, A.; Alexander, T. (), „A Geometric Determination of the Distance to the Galactic Center”, The Astrophysical Journal, 597 (2): L121, arXiv:astro-ph/0306220, Bibcode:2003ApJ...597L.121E, doi:10.1086/380188
Bessel, Friedrich (). „On the parallax of the star 61 Cygni”. London and Edinburgh Philosophical Magazine and Journal of Science. 14: 68–72. Bessel's statement that light employs 10.3 years to traverse the distance.
Ule, Otto (). „Was wir in den Sternen lesen”. Deutsches Museum: Zeitschrift für Literatur, Kunst und Öffentliches Leben. 1: 721–738.
Eisenhauer, F.; Schdel, R.; Genzel, R.; Ott, T.; Tecza, M.; Abuter, R.; Eckart, A.; Alexander, T. (), „A Geometric Determination of the Distance to the Galactic Center”, The Astrophysical Journal, 597 (2): L121, arXiv:astro-ph/0306220, Bibcode:2003ApJ...597L.121E, doi:10.1086/380188
Eisenhauer, F.; Schdel, R.; Genzel, R.; Ott, T.; Tecza, M.; Abuter, R.; Eckart, A.; Alexander, T. (), „A Geometric Determination of the Distance to the Galactic Center”, The Astrophysical Journal, 597 (2): L121, arXiv:astro-ph/0306220, Bibcode:2003ApJ...597L.121E, doi:10.1086/380188