Summerell, Brett, and Edward Liew. “Phytophthora Root Rot: Its Impact in Botanic Gardens and on Threatened Species Conservation”. Sibbaldia: the International Journal of Botanic Garden Horticulture, no. 18 (February 21, 2020): 89-104. Accessed July 15, 2020. https://journals.rbge.org.uk/rbgesib/article/view/290.