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Astron. Astrophys. Suppl. Ser.
Volume 116, Number 3, May_1 1996
Page(s) 403 - 407
VRI photometry of stars in the fields of 12 BL Lacertae objects DOI: 10.1051/aas:1996123

Astronomy and Astrophysics Supplement Series, Vol. 116, May I 1996, 403-407

VRI photometry of stars in the fields of 12 BL Lacertae objects

M. Fiorucci and G. Tosti

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Cattedra di Astrofisica, Università di Perugia, Via A. Pascoli, I-06100 Perugia, Italy

Received July 25; accepted September 8, 1995


We present Johnson-Cousins magnitudes of field comparison stars for twelve BL Lacertae objects belonging to the largest sample of blazars which is monitored at the Perugia University Observatory. The sequences reported here can be used in the long--term CCD photometric monitoring of BL Lac objects aimed to understand the characteristics of their variability. Finding charts for all of these comparison sequences are also included in this paper.

Key words: BL Lacertae objects: general

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