Cristobal Coaguila Berly David, & Barriga Paria Christ Jesus. (2021). Optimization of the Health and Safety Protocol for Covid-19 through the use of the QR Code in the Tailing Disposal System Project, Quellaveco - Moquegua, 2020. International Journal of Engineering and Management Research, 11(5), 129–142. https://doi.org/10.31033/ijemr.11.5.16