Kastner, Joel H.; Vrtilek, Saeqa D.; Soker, Noam (04/2001). “Discovery of Extended X-Ray Emission from the Planetary Nebula NGC 7027 by the Chandra X-Ray Observatory”. The Astrophysical Journal550 (2): L189-L192. arXiv:astro-ph/0102468. Bibcode: 2001ApJ...550L.189K. doi:10.1086/319651.
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Kastner, Joel H.; Vrtilek, Saeqa D.; Soker, Noam (04/2001). “Discovery of Extended X-Ray Emission from the Planetary Nebula NGC 7027 by the Chandra X-Ray Observatory”. The Astrophysical Journal550 (2): L189-L192. arXiv:astro-ph/0102468. Bibcode: 2001ApJ...550L.189K. doi:10.1086/319651.
Masson, C. R. (1989/1). “The structure of NGC 7027 and a determination of its distance by measurement of proper motions”. The Astrophysical Journal336: 294-303. Bibcode: 1989ApJ...336..294M. doi:10.1086/167011.
Bernard Salas, J.; Pottasch, S. R.; Beintema, D. A.; Wesselius, P. R. (2001). “The ISO-SWS spectrum of planetary nebula NGC 7027”. Astronomy and Astrophysics367 (3): 949-958. Bibcode: 2001A&A...367..949B. doi:10.1051/0004-6361:20000435.
Kastner, Joel H.; Vrtilek, Saeqa D.; Soker, Noam (04/2001). “Discovery of Extended X-Ray Emission from the Planetary Nebula NGC 7027 by the Chandra X-Ray Observatory”. The Astrophysical Journal550 (2): L189-L192. arXiv:astro-ph/0102468. Bibcode: 2001ApJ...550L.189K. doi:10.1086/319651.
Masson, C. R. (1989/1). “The structure of NGC 7027 and a determination of its distance by measurement of proper motions”. The Astrophysical Journal336: 294-303. Bibcode: 1989ApJ...336..294M. doi:10.1086/167011.
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