NIKIFOROV, Igor; MALTSEV, Pavel; IVANOV, Vladimir; BARSUK, Inna. Explanation of the express method of the determination of steel grade by spark. ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference, Rezekne, Latvia, v. 1, p. 157–161, 2015. DOI: 10.17770/etr2015vol1.225. Disponível em: https://journals.ru.lv/index.php/ETR/article/view/225.. Acesso em: 6 may. 2024.