James, T.K., A. Rahman, T. Webster, and J. Waller. “Emergence of Weeds As Affected by Vertical Seed Distribution in Arable Soils”. New Zealand Plant Protection 55 (August 1, 2002): 213–217. Accessed August 29, 2026. https://journal.nzpps.org/index.php/nzpp/article/view/3892.