GRB 070508: Swift detection of an intense burst with an optical counterpart. Grupe, D. ; Barthelmy, S. D. ; Chester, M. M. ; Cusumano, G. ; Markwardt, C. B. ; Marshall, F. E. ; Pagani, C. ; Palmer, D. M. ; Racusin, J. L. ; Stamatikos, M. ; Vetere, L. Abstract Publication: GRB Coordinates Network Pub Date: 2007 Bibcode: 2007GCN..6383....1G