NENOV, Nikolay. DEVICE FOR MONITORING THE CONDITION OF THE NATURAL BACKGROUND. ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference, Rezekne, Latvia, v. 2, p. 152–155, 2015. DOI: 10.17770/etr2011vol2.993. Disponível em: https://journals.rta.lv/index.php/ETR/article/view/993.. Acesso em: 28 apr. 2024.