M. Argote et al., RESEARCH NOTE - CCD PHOTOMETRY OF BLAZARS 3C 345, 3C 446 AND 4C 56.27, Revista mexicana de astronomia y astrofisica, 34(2), 1998, pp. 83-86
A photometric study is presented for the quasars 3C 345, 3C 446, and 4
C 56.27, which had previously shown microvariability and which had bee
n proposed as microlensed systems by other authors. Our data for two q
uasars are inserted into their historical light curves, showing a rela
tively recent stage of activity.