Ferrarese, Laura; và đồng nghiệp (1998). “The HST Key Project on the Extragalactic Distance Scale XII. The Discovery of Cepheids and a New Distance to NGC 2541”. The Astrophysical Journal. 507 (2): 655–690. arXiv:astro-ph/9805365. Bibcode:1998ApJ...507..655F. doi:10.1086/306364.
Ferrarese, Laura; và đồng nghiệp (1998). “The HST Key Project on the Extragalactic Distance Scale XII. The Discovery of Cepheids and a New Distance to NGC 2541”. The Astrophysical Journal. 507 (2): 655–690. arXiv:astro-ph/9805365. Bibcode:1998ApJ...507..655F. doi:10.1086/306364.
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Ferrarese, Laura; và đồng nghiệp (1998). “The HST Key Project on the Extragalactic Distance Scale XII. The Discovery of Cepheids and a New Distance to NGC 2541”. The Astrophysical Journal. 507 (2): 655–690. arXiv:astro-ph/9805365. Bibcode:1998ApJ...507..655F. doi:10.1086/306364.