GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission. Karpov, S. ; Beskin, G. ; Bondar, S. ; Ivanov, E. ; Katkova, E. ; Orekhova, N. ; Perkov, A. ; Biryukov, A. ; Sasyuk, V. Abstract Publication: GRB Coordinates Network Pub Date: 2017 Bibcode: 2017GCN.22030....1K