Ngoc Quyen, Hoang Thi, et al. “Effect of Rare Earth on M7C3 Eutectic Carbide in 13% Chromium Alloy Cast Iron”. International Journal on Advanced Science, Engineering and Information Technology, vol. 9, no. 2, Apr. 2019, pp. 724-8, doi:10.18517/ijaseit.9.2.8249.