Eva Villaver et Letizia Stanghellini, « The Survival of Planetary Nebulae in the Intracluster Medium », The Astrophysical Journal, vol. 632, no 2, , p. 854-858 (DOI10.1086/433183, Bibcode2005ApJ...632..854V, lire en ligne [PDF])
I. González-Santamaría, M. Manteiga, A. Manchado, A. Ulla, C. Dafonte et P. López Varela, « Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity », Astronomy & Astrophysics, vol. 656, no A51, , p. 21 pages (DOI10.1051/0004-6361/202141916, Bibcode2021A&A...656A..51G, lire en ligne [PDF])
C. R. O'Dell, F. Sabbadin et W. J. Henney, « The Three-Dimensional Ionization Structure and Evolution of NGC 6720, The Ring Nebula », The Astronomical Journal, vol. 134, no 4, , p. 1679-1692 (DOI10.1086/521823, Bibcode2007AJ....134.1679O, lire en ligne [PDF])
Eva Villaver et Letizia Stanghellini, « The Survival of Planetary Nebulae in the Intracluster Medium », The Astrophysical Journal, vol. 632, no 2, , p. 854-858 (DOI10.1086/433183, Bibcode2005ApJ...632..854V, lire en ligne [PDF])
R. L. M. Corradi, D. Schönberner, M. Steffen et M. Perinotto, « Ionized haloes in planetary nebulae: new discoveries, literature compilation and basic statistical properties », Monthly Notices of the Royal Astronomical Society, vol. 340, no 2, , p. 417-446 (DOI10.1046/j.1365-8711.2003.06294.x, lire en ligne [html])
I. González-Santamaría, M. Manteiga, A. Manchado, A. Ulla, C. Dafonte et P. López Varela, « Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity », Astronomy & Astrophysics, vol. 656, no A51, , p. 21 pages (DOI10.1051/0004-6361/202141916, Bibcode2021A&A...656A..51G, lire en ligne [PDF])
harvard.edu
ui.adsabs.harvard.edu
C. R. O'Dell, F. Sabbadin et W. J. Henney, « The Three-Dimensional Ionization Structure and Evolution of NGC 6720, The Ring Nebula », The Astronomical Journal, vol. 134, no 4, , p. 1679-1692 (DOI10.1086/521823, Bibcode2007AJ....134.1679O, lire en ligne [PDF])
C. R. O'Dell, B. Balick, A. R. Hajian, W. J. Henney et A. Burkert, « Knots in Planetary Nebulae », Revista Mexicana de Astronomía y Astrofísica, (Serie de Conferencias), vol. 15, , p. 29-33 (Bibcode2003RMxAC..15...29O)
William Huggins et W. A. Miller, « On the Spectra of Some of the Nebulae. By William Huggins, F.R.A.S. A Supplement to the Paper "On the Spectra of Some of the Fixed Stars William Huggins F.R.A.S., and W. A. Miller, M.D., LL.D., Treas. and V.P.P.S." », Philosophical Transactions of the Royal Society of London, vol. 154, , p. 437-444 (Bibcode1864RSPT..154..437H, lire en ligne [PDF])
Eva Villaver et Letizia Stanghellini, « The Survival of Planetary Nebulae in the Intracluster Medium », The Astrophysical Journal, vol. 632, no 2, , p. 854-858 (DOI10.1086/433183, Bibcode2005ApJ...632..854V, lire en ligne [PDF])
I. González-Santamaría, M. Manteiga, A. Manchado, A. Ulla, C. Dafonte et P. López Varela, « Planetary nebulae in Gaia EDR3: Central star identification, properties, and binarity », Astronomy & Astrophysics, vol. 656, no A51, , p. 21 pages (DOI10.1051/0004-6361/202141916, Bibcode2021A&A...656A..51G, lire en ligne [PDF])
iop.org
iopscience.iop.org
C. R. O'Dell, F. Sabbadin et W. J. Henney, « The Three-Dimensional Ionization Structure and Evolution of NGC 6720, The Ring Nebula », The Astronomical Journal, vol. 134, no 4, , p. 1679-1692 (DOI10.1086/521823, Bibcode2007AJ....134.1679O, lire en ligne [PDF])
R. L. M. Corradi, D. Schönberner, M. Steffen et M. Perinotto, « Ionized haloes in planetary nebulae: new discoveries, literature compilation and basic statistical properties », Monthly Notices of the Royal Astronomical Society, vol. 340, no 2, , p. 417-446 (DOI10.1046/j.1365-8711.2003.06294.x, lire en ligne [html])
royalsocietypublishing.org
William Huggins et W. A. Miller, « On the Spectra of Some of the Nebulae. By William Huggins, F.R.A.S. A Supplement to the Paper "On the Spectra of Some of the Fixed Stars William Huggins F.R.A.S., and W. A. Miller, M.D., LL.D., Treas. and V.P.P.S." », Philosophical Transactions of the Royal Society of London, vol. 154, , p. 437-444 (Bibcode1864RSPT..154..437H, lire en ligne [PDF])