Fantz, U., Behringer, K., Gafert, J., Coster, D., & ASDEX Upgrade Team (1999). Optical emission measurements of H2 and D2 molecules in the divertor region of ASDEX Upgrade. Journal of Nuclear Materials, 266-269, 490-494. doi:10.1016/S0022-3115(98)00540-6.