RISK ANALYSIS OF THE PILLAR STRENGTH IN THE ESTONIA MINE. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, [S. l.], v. 1, p. 19–23, 2015. DOI: 10.17770/etr2009vol1.1113. Disponível em: https://archive-journals.rtu.lv/etr/article/view/3666.. Acesso em: 11 mar. 2026.