Tanhan P, Pokethitiyook P, Kruatrachue M, Chaiyarat R, Upatham S. Effects of Soil Amendments and EDTA on Lead Uptake byChromolaena Odorata: Greenhouse and Field Trial Experiments. International Journal of Phytoremediation. 2011 Oct;13(9):897–911. doi: 10.1080/15226514.2010.525556.