Stroth, U., Baldzuhn, J., Geiger, J., Geist, T., Giannone, L., Hartfuß, H. J., et al. (1998). High-confinement NBI discharges in the W7-AS stellarator. Plasma Physics and Controlled Fusion, 40(8), 1551-1565. doi:10.1088/0741-3335/40/8/008.