Gardi, C., S. Brenna, S. Solaro, M. Piazzi, and F. Petrella. “The Carbon Sequestration Potential of Soils: Some Data from Northern Italian Regions”. Italian Journal of Agronomy, vol. 2, no. 2, June 2007, pp. 143-50, doi:10.4081/ija.2007.143.