Daniel J. Majaess, David G. Turner, David J. Lane: In Search of Possible Associations between Planetary Nebulae and Open Clusters. Publications of the Astronomical Society of the Pacific, 2007-12, nro 862, s. 1349–1360. doi:10.1086/524414ISSN 0004-6280Artikkelin verkkoversio.
L. L. Kiss, Gy M. Szabo, Z. Balog, Q. A. Parker, D. J. Frew: 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, 21.11.2008, nro 1, s. 399–404. doi:10.1111/j.1365-2966.2008.13899.xArtikkelin verkkoversio.
Daniel J. Majaess, David G. Turner, David J. Lane: In Search of Possible Associations between Planetary Nebulae and Open Clusters. Publications of the Astronomical Society of the Pacific, 2007-12, nro 862, s. 1349–1360. doi:10.1086/524414ISSN 0004-6280Artikkelin verkkoversio.
L. L. Kiss, Gy M. Szabo, Z. Balog, Q. A. Parker, D. J. Frew: 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, 21.11.2008, nro 1, s. 399–404. doi:10.1111/j.1365-2966.2008.13899.xArtikkelin verkkoversio.
Guy McArthur, Hartmut Frommert, Christine Kronberg: NGC 2438www.messier.seds.org. Viitattu 19.5.2018.
worldcat.org
Daniel J. Majaess, David G. Turner, David J. Lane: In Search of Possible Associations between Planetary Nebulae and Open Clusters. Publications of the Astronomical Society of the Pacific, 2007-12, nro 862, s. 1349–1360. doi:10.1086/524414ISSN 0004-6280Artikkelin verkkoversio.