INDUSTRY 4.0 - DEVELOPMENT AND CONSEQUENCES FOR SUSTAINABLE DEVELOPMENT OF BULGARIA. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, [S. l.], v. 3, p. 245–251, 2021. DOI: 10.17770/etr2021vol3.6543. Disponível em: https://archive-journals.rtu.lv/etr/article/view/4518.. Acesso em: 11 mar. 2026.