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We report the results of optical monitoring of a sample of AGNs carried out in summer 2002. While rapid optical variability is a well-known aspect of blazar activity, there have been fewer studies of possible rapid variations in the spectrum, although some studies suggest that variations may exist even on scales of hours and less. Six of fourteen objects studied show some degree of variability of...
We present a revised and augmented version of the Gonzalez-Perez et al. [AJ 122 (2001) 2055] catalogue of stars in quasar and blazar fields calibrated in the Landolt system. Several of the sources in this catalogue are known TeV emitters and thus of considerable interest for multifrequency campaigns. A total of 8000 measures in BVRI have been added, mostly of previously poorly observed fields giving...
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