A plasmapause-like density boundary at high latitudes in Saturn's magnetosphere - Gurnett,DA; Persoon,AM; Kopf,AJ; Kurth,WS; Morooka,MW; Wahlund,J-E; Khurana,KK; Dougherty,MK; Mitchell,DG; Krimigis,SM; Krupp,N (GEOPHYSICAL RESEARCH LETTERS, 2010)