Faber, B. J., Pueschel, M. J., Proll, J. H. E., Xanthopoulos, P., Terry, P. W., Hegna, C. C., et al. (2015). Gyrokinetic studies of trapped electron mode turbulence in the Helically Symmetric eXperiment stellarator. Physics of Plasmas, 22: 072305. doi:10.1063/1.4926510.