GRB 050721A: early swift XRT analysis results. Romano, P. ; Antonelli, L. A. ; Chincarini, G. ; Moretti, A. ; Tagliaferri, G. ; Page, K. ; Marshall, F. ; Boyd, P. Abstract Publication: GRB Coordinates Network Pub Date: 2005 Bibcode: 2005GCN..3659....1R