Long-term optical and radio variability of BL Lacertae

Y. C. Guo, S. M. Hu, C. Xu +6

Well-sampled optical and radio light curves of BL Lacertae in B, V, R, I bands and 4.8, 8.0, 14.5 GHz from 1968 to 2014 were presented in this paper. A possible $1.26\pm 0.05$ yr…