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de Zeeuw, P. T.; Hoogerwerf, R.; de Bruijne, J. H. J.; Brown, A. G. A.; Blaauw, A. (1999). “A HIPPARCOS Census of the Nearby OB Associations”. The Astronomical Journal117 (1): 354–399. arXiv:astro-ph/9809227. Bibcode: 1999AJ....117..354D. doi:10.1086/300682.