IceCube-190221A: Swift-XRT Follow-up Observations. Keivani, A. ; Evans, P. A. ; Fox, D. B. ; Kennea, J. A. ; Cowen, D. F. ; Osborne, J. P. ; Marshall, F. E. ; Santander, M. ; Mostafa, M. ; Ayala, H. Abstract Publication: GRB Coordinates Network Pub Date: 2019 Bibcode: 2019GCN.23925....1K