Gruber, O., Fahrbach, H.-U., Gehre, O., Herrmann, W., Kaufmann, M., Lackner, K., et al. (1988). Auxiliary Heated Multipellet-Fuelled Discharges in ASDEX and Influence of Density Profile Shape on Confinement. Plasma Physics and Controlled Fusion, 30(11), 1611-1623.