Xu, Y., Shesterikov, I., Van Schoor, M., Vergote, M., Weynants, R. R., Krämer-Flecken, A., et al. (2011). Observation of geodesic acoustic modes (GAMs) and their radial propagation at the edge of the TEXTOR tokamak. Plasma Physics and Controlled Fusion, 53: 095015 (13pp). doi:10.1088/0741-3335/53/9/095015.