Illingworth, G. D.; Magee, D.; Oesch, P. A.; Bouwens, R. J.; Labbé, I.; Stiavelli, M.; van Dokkum, P. G.; Franx, M.; Trenti, M.; Carollo, C. M.; Gonzalez, V. The HST eXtreme Deep Field XDF: Combining all ACS and WFC3/IR Data on the HUDF Region into the Deepest Field Ever. The Astrophysical Journal Supplement Series. 21 October 2013, 209 (1): 6. Bibcode:2013ApJS..209....6I. S2CID 55052332. arXiv:1305.1931. doi:10.1088/0067-0049/209/1/6.
astropix.com
Lodriguss, Jerry. M33 (Triangulum Galaxy). 1993 [2009-11-27]. (原始内容存档于2010-01-15). (shows b mag not v mag)
Illingworth, G. D.; Magee, D.; Oesch, P. A.; Bouwens, R. J.; Labbé, I.; Stiavelli, M.; van Dokkum, P. G.; Franx, M.; Trenti, M.; Carollo, C. M.; Gonzalez, V. The HST eXtreme Deep Field XDF: Combining all ACS and WFC3/IR Data on the HUDF Region into the Deepest Field Ever. The Astrophysical Journal Supplement Series. 21 October 2013, 209 (1): 6. Bibcode:2013ApJS..209....6I. S2CID 55052332. arXiv:1305.1931. doi:10.1088/0067-0049/209/1/6.
Illingworth, G. D.; Magee, D.; Oesch, P. A.; Bouwens, R. J.; Labbé, I.; Stiavelli, M.; van Dokkum, P. G.; Franx, M.; Trenti, M.; Carollo, C. M.; Gonzalez, V. The HST eXtreme Deep Field XDF: Combining all ACS and WFC3/IR Data on the HUDF Region into the Deepest Field Ever. The Astrophysical Journal Supplement Series. 21 October 2013, 209 (1): 6. Bibcode:2013ApJS..209....6I. S2CID 55052332. arXiv:1305.1931. doi:10.1088/0067-0049/209/1/6.
Illingworth, G. D.; Magee, D.; Oesch, P. A.; Bouwens, R. J.; Labbé, I.; Stiavelli, M.; van Dokkum, P. G.; Franx, M.; Trenti, M.; Carollo, C. M.; Gonzalez, V. The HST eXtreme Deep Field XDF: Combining all ACS and WFC3/IR Data on the HUDF Region into the Deepest Field Ever. The Astrophysical Journal Supplement Series. 21 October 2013, 209 (1): 6. Bibcode:2013ApJS..209....6I. S2CID 55052332. arXiv:1305.1931. doi:10.1088/0067-0049/209/1/6.