Von Ludwig, C.F.H. (1831) “List of exotic trees, shrubs, plants, bulbs; garden flower, forest, and other seeds: imported lately from Germany (Wurtemberg and Hamburg), Holland, &c. by the Danish Ship Norden, Capt. Burd, and the Ionia, Capt. C. Buck”, South African Quarterly Journal, 1(5), pp. 40–45. doi:10.21504/saqj.15.2598.