Nature 486, 243–246 (2012); doi:10.1038/nature11074

In this Letter, the name of Joerg R. Jinschek (FEI Europe, Europe NanoPort, Achtseweg Noord 5, 5651 CG Eindhoven, The Netherlands) should be included in the author list. On page 244, this sentence should be deleted: “The experimental data were obtained from ref. 11.”. The Author Contributions section should include the sentence: “J.R.J. provided the experimental images of graphene.”. The Acknowledgements section should include the sentence: “J.R.J. thanks E. Yucelen, R. Dunin-Borkowski and Ch. Kisielowski for support, and N. Alem and A. Zettl for the gift of the graphene sample.”. The PDF and HTML versions of the original paper have been corrected online.