... 1.5

Based on observations collected at the ISO Observatory, Canada-France-Hawaii Telescope, Australia Telescope Compact Array, UKIRT, ROSAT and the European Southern Observatory (prg: 58.E-0885, 61.B-0369, 265.B-5005).

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...$1.4 \pm 0.12$

The value quoted in Pierre et al. (1996) is incorrect.

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