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NGC 2438 | ScienceBlogs
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https://arxiv.org/abs/1109.5609
[1109.5609] The Ionization State of the Halo Planetary Nebula NGC 2438
Abstract page for arXiv paper 1109.5609: The Ionization State of the Halo Planetary Nebula NGC 2438
planetary nebula11095609ionizationstate