Siebold, P.F. von & Zuccarini, J.G. in Siebold, P.F. von (1835), Flora Japonica 1: 25 [tax. nov.]

• Type: Paulownia imperialis Siebold & Zucc.

Tovey, J.R. & Morris, P.F. (1922), Contributions from the National Herbarium of Victoria, No. 2. Proceedings of the Royal Society of Victoria 35(1): 87 [secondary reference]

Cronquist, A.J. (1981), An Integrated System of Classification of Flowering Plants: 953, 970 [secondary reference]

Fischer, E. in Kubitzki, K. (ed.) (2004), Scrophulariaceae. The Families and Genera of Vascular Plants 7: 374, Fig. 43D, 49B [secondary reference]

Mabberley, D.J. (1 May 2008), Mabberley's Plant-Book Edn. 3: 638 [secondary reference]

Council of Heads of Australasian Herbaria (2010), Australian Plant Census: - APC [secondary reference]

• APC Dist.: Qld (naturalised)

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