...sources

Based on observations collected at the TIRGO (Gornergrat, Switzerland) operated by the CAISMI-CNR, Firenze, Italy, and at the NOT (La Palma, Canary Islands) operated by the Nordic Optical Telescope Scientific Association (Denmark, Finland, Norway, Sweden).

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...Testi¹

This research was partly conducted while L. Testi was at the Dipartimento di Astronomia e Scienza dello Spazio, Università degli Studi di Firenze, Largo E. Fermi 5, I-50125, Firenze, Italy.

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...IRAF

IRAF is made available to the astronomical community by the National Optical Astronomy Observatories, which are operated by AURA, Inc., under contract with the U.S. National Science Foundation.

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