Pieri, L.; Ventura, F.; Ventura, M.; Tagliavini, M.; Ponti, M.; Pistocchi, R.; Albertazzi, S.; Vignudelli, M.; Rossi Pisa, P. Chemical and Biological Indicators of Water Quality in Three Agricultural Watersheds of the Po Valley, Italy. Ital J Agronomy 2011, 6, e36.