Partly based on observations with the NASA/ESA Hubble Space Telescope performed at the STScI which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

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Partly based on observations with the International Ultraviolet Explorer (IUE).

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...3,

Visiting Astronomer at Cerro Tololo Inter-American Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with the NSF.

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