GCN Circular 15425
L. P. Xin, J. Y. Wei, Y. L. Qiu, J. S. Deng, J. Wang, X. H. Han and C. Wu on behalf of EAFON report: We began to observe GRB 131030A (Troja et al. GCN 15402) with Xinglong 0.8-m TNT telescope at 13:59:04 (UT) , Oct. 31th, about 17 hours after the burst. 10*300 sec R-band images were obtained. The optical counterpart (Troja et al. GCN 15402) was clearly detected with a magnitude of 19.4+/-0.1 mag in R band, calibrated by USNO B1.0 R2mag at the mean time of 17.397h after the burst. This message may be cited.