Ilyin, A., and B. Borisov. “GRAIN-BOUNDARY SULPHUR SEGREGATION AND EMBRITTLEMENT OF HIGH-PURITY NICKEL”. Recent Contributions to Physics, vol. 2018, no. 2, Nov. 2018, pp. 59-64, https://bph.kaznu.kz/index.php/zhuzhu/article/view/1040.