... effects[*]
Based on observations made with the 2 m telescope of the Thüringer Landessternwarte Tautenburg.
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... QSOs[*]
In this paper, the terms quasar and QSO are used as synonyms for star-like objects with $M_B\le-23$(H0=50 kms-1Mpc-1 and q0=0).
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Copyright ESO 2001