GCN Circular 23628
A. Noschese (AC-OASDG), L. Izzo (IAA-CSIC), A. Di Dato and L. D���Avino (AC-OASDG) report: We observed the field of GRB 190106A (Sonbas et al. GCN 23615) with the 0.5m telescope of the Osservatorio Astronomico S. Di Giacomo located in Agerola, Italy ( https://goo.gl/Dqvqhf ). We obtained a series of 3x180 s images in the Rc filter, starting at 21:44:38 UT, ~ 8.17 hrs after the GRB detection. In our stacked image, we find a source at the position of the observed optical counterpart (Lipunov et al. GCN 23616, Itoh et al. GCN 23617, Mao et al. GCN 23618, Reva et al., GCN 23620, Xin et al. GCN 23622, Quadri et al. GCN 23624, Hu et al. GCN 23627) for which we measure a magnitude of Rc(AB) = 19.47 +/- 0.10 mag. The calibration was performed using nearby stars in the USNO B1 catalog.