Singhurst, Jason R., Jeffrey N. Mink, Katy Emde, Lan Shen, Don Verser, and Walter C. Holmes. “A”. Journal of the Botanical Research Institute of Texas 12, no. 2 (November 20, 2018): 721–733. Accessed April 19, 2024. https://journals.brit.org/jbrit/article/view/976.