Beechey-Gradwell, Zac D, Somrutai Winichayakul, and Nick J Roberts. “High Lipid Perennial Ryegrass Growth under Variable Nitrogen, Water and Carbon Dioxide Supply”. Journal of New Zealand Grasslands 80 (December 5, 2018): 219–224. Accessed June 3, 2026. https://www.nzgajournal.org.nz/index.php/JoNZG/article/view/349.