Erratum: Crossover of the three-dimensional topological insulator Bi 2Se3 to the two-dimensional limit (Nature Physics (2010) 6 (584-588)) - Yi Zhang; Ke He; Cui-Zu Chang; Can-Li Song; Li-Li Wang; Xi Chen; Jin-Feng Jia; Zhong Fang; Xi Dai; Wen-Yu Shan; Shun-Qing Shen; Qian Niu; et al. (Nature Physics, 2010)