Hardy, Graham. ““To Get Those Plants . Likely to Prove Interesting at Edinburgh": Robert Brown of Perth and James McNab’s North American Tour of 1834”. Sibbaldia: the International Journal of Botanic Garden Horticulture, no. 9 (October 31, 2011): 191–222. Accessed May 2, 2024. https://journals.rbge.org.uk/rbgesib/article/view/131.