Macri, L. M. (2006). "A New Cepheid Distance to the Maser-Host Galaxy NGC 4258 and Its Implications for the Hubble Constant". The Astrophysical Journal. 652 (2). ss. 1133-1149. Bibcode:2006ApJ...652.1133M. doi:10.1086/508530.
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Macri, L. M. (2006). "A New Cepheid Distance to the Maser-Host Galaxy NGC 4258 and Its Implications for the Hubble Constant". The Astrophysical Journal. 652 (2). ss. 1133-1149. Bibcode:2006ApJ...652.1133M. doi:10.1086/508530.