Canchari Silverio, Godelia, and Oswaldo Ortiz Sanchez. “Recovery of Solid Waste in the University City of the National University of San Marcos”. Revista Del Instituto De investigación De La Facultad De Minas, Metalurgia Y Ciencias geográficas, vol. 11, no. 21, July 2008, pp. 95-99, https://doi.org/10.15381/iigeo.v11i21.521.