L. C. Ho; A. V. Filippenko; W. L. W. Sargent «A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies». Astrophysical Journal Supplement, 112, 2, 1997, pàg. 315–390. arXiv: astro-ph/9704107. Bibcode: 1997ApJS..112..315H. DOI: 10.1086/313041.
caltech.edu
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"A Near-Infrared Atlas of Spiral Galaxies", Debra Meloy Elmegreen, "CH3. Discussion" (accedit el 23 d'abril de 2010)
L. C. Ho; A. V. Filippenko; W. L. W. Sargent «A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies». Astrophysical Journal Supplement, 112, 2, 1997, pàg. 315–390. arXiv: astro-ph/9704107. Bibcode: 1997ApJS..112..315H. DOI: 10.1086/313041.
L. C. Ho; A. V. Filippenko; W. L. W. Sargent «A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies». Astrophysical Journal Supplement, 112, 2, 1997, pàg. 315–390. arXiv: astro-ph/9704107. Bibcode: 1997ApJS..112..315H. DOI: 10.1086/313041.