Cluster and TC-1 observation of magnetic holes in the plasma sheet - Sun, WJ; Shi, QQ; Fu, SY; Pu, ZY; Dunlop, MW; Walsh, AP; Zong, QG; Xiao, T; Tang, CL; Reme, H; Carr, C; Lucek, E; et al. (ANNALES GEOPHYSICAE, 2012)