Kiss, L. L.; Szabó, Gy. M.; Balog, Z.; Parker, Q. A.; Frew, D. J. (November 2008). ”AAOmega radial velocities rule out current membership of the planetary nebula NGC 2438 in the open cluster M46”. Monthly Notices of the Royal Astronomical Society 391 (1): sid. 399–404. doi:10.1111/j.1365-2966.2008.13899.x. Bibcode: 2008MNRAS.391..399K.
Mermilliod, J.-C.; Clariá, J. J.; Andersen, J.; Piatti, A. E.; Mayor, M. (August 2001). ”Red giants in open clusters. IX. NGC 2324, 2818, 3960 and 6259”. Astronomy and Astrophysics 375: sid. 30–39. doi:10.1051/0004-6361:20010845]. Bibcode: 2001A&A...375...30M.
Öttl, S.; Kimeswenger, S.; Zijlstra, A. A. (May 2014). ”Ionization structure of multiple-shell planetary nebulae. I. NGC 2438”. Astronomy & Astrophysics 565: sid. 13. doi:10.1051/0004-6361/201323205. A87. Bibcode: 2014A&A...565A..87O.
Dalnodar, Silvia (August 2012). "The ionization state of the halo planetary nebula NGC 2438" in Planetary Nebulae: An Eye to the Future, Proceedings of the International Astronomical Union, IAU Symposium. {{{booktitle}}}283: 338–339. DOI:10.1017/S1743921312011313.
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Kiss, L. L.; Szabó, Gy. M.; Balog, Z.; Parker, Q. A.; Frew, D. J. (November 2008). ”AAOmega radial velocities rule out current membership of the planetary nebula NGC 2438 in the open cluster M46”. Monthly Notices of the Royal Astronomical Society 391 (1): sid. 399–404. doi:10.1111/j.1365-2966.2008.13899.x. Bibcode: 2008MNRAS.391..399K.
Mermilliod, J.-C.; Clariá, J. J.; Andersen, J.; Piatti, A. E.; Mayor, M. (August 2001). ”Red giants in open clusters. IX. NGC 2324, 2818, 3960 and 6259”. Astronomy and Astrophysics 375: sid. 30–39. doi:10.1051/0004-6361:20010845]. Bibcode: 2001A&A...375...30M.
Öttl, S.; Kimeswenger, S.; Zijlstra, A. A. (May 2014). ”Ionization structure of multiple-shell planetary nebulae. I. NGC 2438”. Astronomy & Astrophysics 565: sid. 13. doi:10.1051/0004-6361/201323205. A87. Bibcode: 2014A&A...565A..87O.
Corradi, R. L. M.; Schönberner, D.; Steffen, M.; Perinotto, M. (February 2000). Manchado, A.; Stanghellini, L.; Schoenberner, D.. red. ”A hydrodynamical study of multiple-shell planetaries . I. NGC 2438”. Astronomy and Astrophysics 354: sid. 1071–1085. Bibcode: 2000A&A...354.1071C.