Panchal, V*; Burnett, T L; Pearce, R*; Cedergren, K*; Yakimova, R*; Tzalenchuk, A; Kazakova, O (2012) Surface potential variations in epitaxial graphene devices investigations by electrostatic force spectroscopy. In: 2012 IEEE 12th International Conference on Nanotechnology (IEEE-NANO), 20-23 August 2012, Birmingham, UK.