7Alber A. Sadek,Masao Ushio,Fukuhisa Matsuda.Effect of rare earth metal oxide additions to tungsten electrodes[J]. Metallurgical Transactions A . 1990 (12)
8Sadek AA,Ushio M,and Matsuda F.Effect of Rare Earth Metal Oxide Additions of Tungsten Electrodes. Metallurgicel Transactions A . 1990