Real Time Safeguard of Workers in Coal Mining using Wireless Sensor Networks and RFID. International Journal of Current Engineering and Technology, [S. l.], v. 5, n. 4, p. 2671–2675, 2015. DOI: 10.14741/. Disponível em: https://ijcet.evegenis.org/index.php/ijcet/article/view/2750. Acesso em: 6 apr. 2026.