GRB020531: second /session define format EPOCH1 = Chandra observations. Butler, N. ; Dullighan, A. ; Ford, P. ; Monnelly, G. ; Ricker, G. ; Vanderspek, R. ; Lamb, D. Abstract Publication: GRB Coordinates Network Pub Date: 2002 Bibcode: 2002GCN..1426....1B