Physicochemical or geochemical

• Gomez, D., Smichowski, P., Polla, G., Ledesma, A., Resnizky, S., Rosa, S., (2002), Fractionation of elements by particle size of ashes ejected from Copahue Volcano, Argentina, Journal of Environmental Monitoring, 4(6), 972-977, 10.1039/B207080B