Microscopy of hydrogen and hydrogen-vacancy defect structures on graphene devices - Wong, D; Wang, Y; Jin, W; Tsai, H-Z; Bostwick, A; Rotenberg, E; Kawakami, R; Zettl, A; Mostofi, A; Lischner, J; Crommie, M (Physical review B: Condensed matter and materials physics, 2018)