Trigger 554491: Swift detection of a spike possibly from Sgr a*. Barthelmy, S. D. ; Kennea, J. A. ; Krimm, H. A. ; Mangano, V. ; Markwardt, C. B. ; Marshall, F. E. ; Maselli, A. Abstract Publication: GRB Coordinates Network Pub Date: 2013 Bibcode: 2013GCN.14443....1B