Windisch, T., Krämer-Flecken, A., Velasco, J. L., Könies, A., Nührenberg, C., Grulke, O., et al. (2017). Poloidal correlation reflectometry at W7-X: radial electric field and coherent fluctuations. Plasma Physics and Controlled Fusion, 59: 105002. doi:10.1088/1361-6587/aa759b.