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Nordgren, Tyler E. et al. (1999). “Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer”. The Astronomical Journal118 (6): 3032-3038. Bibcode: 1999AJ....118.3032N. doi:10.1086/301114. ISSN00046256.
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Nordgren, Tyler E. et al. (1999). “Stellar Angular Diameters of Late-Type Giants and Supergiants Measured with the Navy Prototype Optical Interferometer”. The Astronomical Journal118 (6): 3032-3038. Bibcode: 1999AJ....118.3032N. doi:10.1086/301114. ISSN00046256.