Drozdovsky, I. O.; Karachentsev, I. D. (2000). “Photometric distances to six bright resolved galaxies”. Astronomy and Astrophysics Supplement. 142 (3): 425–432. Bibcode:2000A&AS..142..425D. doi:10.1051/aas:2000155.
R. M. Gonzalez Delgado; E. Perez; C. Tadhunter; J. M. Vilchez; J. M. Rodriguez-Espinosa (2000). “H II Region Population in a Sample of Nearby Galaxies with Nuclear Activity. I. Data and General Results”. Astrophysical Journal Supplement. 108 (1): 155. Bibcode:1997ApJS..108..155G. doi:10.1086/312951.
harvard.edu
ui.adsabs.harvard.edu
Drozdovsky, I. O.; Karachentsev, I. D. (2000). “Photometric distances to six bright resolved galaxies”. Astronomy and Astrophysics Supplement. 142 (3): 425–432. Bibcode:2000A&AS..142..425D. doi:10.1051/aas:2000155.
R. M. Gonzalez Delgado; E. Perez; C. Tadhunter; J. M. Vilchez; J. M. Rodriguez-Espinosa (2000). “H II Region Population in a Sample of Nearby Galaxies with Nuclear Activity. I. Data and General Results”. Astrophysical Journal Supplement. 108 (1): 155. Bibcode:1997ApJS..108..155G. doi:10.1086/312951.