Obolenskii, M. A.; Bondarenko, A. V.; Shklovskij, V. A.; Revyakina, M. G. Anisotropy of the Critical Curremt Due to Twin Planes and Vortex Melting in YBa₂Cu₃O_7-x Single Crystals. Fiz. Nizk. Temp. 1996, 22, 892-897.