Groening, D. E. Experimental Plasma Physics 3 (E3), Max Planck Institute for Plasma Physics, Max Planck Society;
IPP_III_41.pdf (Any fulltext), 9MB
Groening, D. E., Gottardi, N., & Rossetti, E.(1978). Unmodulated Interferometer (IPP III/41). Garching (DE): Max-Planck-Institut für Plasmaphysik.