Harrington, K., D. Horne, and P. Kemp. “Can Differences in <i>Cirsium arvense</i> and <i>Rumex obtusifolius</i> Densities Within Pastures Be Explained by Soil Parameters”. New Zealand Plant Protection, vol. 67, Jan. 2014, pp. 238-44, doi:10.30843/nzpp.2014.67.5786.