The motion, multiplication and annihilation of dislocations was studied  in situ  by using a spatially-resolved photoluminescence technique, at temperatures of between 4.2 and 77K, while the crystals were deformed in the prismatic glide system. The true dislocation structure and its features, in crystals which had been deformed on the basal dislocation glide system, were identified here for the first time.

V.D.Negrii, J.A.Osipyan, N.V.Lomak: Physica Status Solidi A, 1991, 126[1], 49-61