...Helfand

Visiting Astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatory

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...NRAO

The National Radio Astronomy Observatory is operated by Associated Universities, Inc., under cooperative agreement with the National Science Foundation

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...FIRST

The FIRST Survey World Wide Web homepage is http://sundog.stsci.edu

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...Observatory,

Kitt Peak National Observatory, NOAO, is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), under cooperative agreement with the National Science Foundation

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