Bosch, H.-S., Wolf, R., Andreeva, T., Baldzuhn, J., Birus, D., Bluhm, T., et al. (2013). Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X. Nuclear Fusion, 53: 126001 (15pp). doi:10.1088/0029-5515/53/12/126001.