GRB 141220A: Redshift from OSIRIS at the 10.4m GTC. de Ugarte Postigo, A. ; Thoene, C. C. ; Gorosabel, J. ; Tanvir, N. ; Fynbo, J. P. U. ; Pesev, P. ; Gomez Velarde, G. ; Perez Valladares, D. Abstract Publication: GRB Coordinates Network Pub Date: 2014 Bibcode: 2014GCN.17198....1D