Cremonese, G.; Boehnhardt, H.; Crovisier, J. et al. (1997). “Neutral Sodium from Comet Hale-Bopp: A Third Type of Tail”. The Astrophysical Journal490 (2): L199–L202. arXiv:astro-ph/9710022. doi:10.1086/311040. ISSN0004637X.
Neugebauer, M. et al. (2007). “Encounter of the Ulysses Spacecraft with the Ion Tail of Comet MCNaught”. The Astrophysical Journal667 (2): 1262–1266. Bibcode: 2007ApJ...667.1262N. doi:10.1086/521019.
Cremonese, G.; Boehnhardt, H.; Crovisier, J. et al. (1997). “Neutral Sodium from Comet Hale-Bopp: A Third Type of Tail”. The Astrophysical Journal490 (2): L199–L202. arXiv:astro-ph/9710022. doi:10.1086/311040. ISSN0004637X.
Neugebauer, M. et al. (2007). “Encounter of the Ulysses Spacecraft with the Ion Tail of Comet MCNaught”. The Astrophysical Journal667 (2): 1262–1266. Bibcode: 2007ApJ...667.1262N. doi:10.1086/521019.
Cremonese, G.; Boehnhardt, H.; Crovisier, J. et al. (1997). “Neutral Sodium from Comet Hale-Bopp: A Third Type of Tail”. The Astrophysical Journal490 (2): L199–L202. arXiv:astro-ph/9710022. doi:10.1086/311040. ISSN0004637X.