Rights:
© 2001 American Physical Society (APS). This is the accepted version of the following article: Foster, Adam S. ; Barth, C. ; Shluger, A. L. ; Reichling, M.. 2001. Unambiguous Interpretation of Atomically Resolved Force Microscopy Images of an Insulator. Physical Review Letters. Volume 86, Issue 11. 2373-2376. ISSN 0031-9007 (printed). DOI: 10.1103/physrevlett.86.2373, which has been published in final form at http://journals.aps.org/prl/pdf/10.1103/PhysRevLett.86.2373.