Extraordinary field-aligned current signatures in Saturn's high-latitude magnetosphere: Analysis of Cassini data during Revolution 89 - Bunce, EJ; Cowley, SWH; Talboys, DL; Dougherty, MK; Lamy, L; Kurth, WS; Schippers, P; Cecconi, B; Zarka, P; Arridge, CS; Coates, AJ (JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2010)