Cortés, José L., et al. “The Color of Urban Dust As an Indicator of Contamination by Potentially Toxic Elements: The Case of Ensenada, Baja California, Mexico”. Revista Chapingo Serie Ciencias Forestales Y Del Ambiente, vol. 21, no. 3, Sept. 2015, pp. 255-66, doi:10.5154/r.rchscfa.2015.02.003.