GCN Circular 15976
S. Leonini, P. Rosi, M. Conti, G. Guerrini and L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy) report: We observed the field of GRB140311A (Swift trigger 591390, Racusin et al., GCN Circ. 15944) with the automatic 0.53m RC telescope + U47 detector at Montarrenti Observatory (Siena, Italy, IAU code C88). The observations were started at 2014-03-12 00:20:19 UT (approximately 3 hours post-burst) stacking 5 unfiltered CCD exposures of 60s each. We have not found optical transient within the error-box given by Swift. Mag. upper limit R = 20.02+/-0.16 Magnitudes were obtained using Astrometrica software using USNO-B1 catalogue and are not corrected for galactic extinction. The message may be cited.