Moore, S. le M. (July 1912), The genus Crassocephalum. Journal of Botany, British and Foreign 50: 211-212 [comb. nov.]

basionym: Gynura crepidioides Benth. legitimate

Everist, S.L. (1960), Two new records of plant pests. Proceedings of the Royal Society of Queensland 71: v. [secondary reference]

Steenis, C.G.G.J. van (1967), Notes on the introduction of Crassocephalum crepidioides (Bth.) S. Moore in Indo-Australia (COMPOSITAE). Journal of the Indian Botanical Society 66: 463-469 [secondary reference]

Henderson, R.J.F. (1973), Crassocephalum crepidioides (Benth.) S. Moore in Australia. Proceedings of the Royal Society of Queensland 84: 55-60, T. 5 [secondary reference]

Koster, J.T. (1980), The Compositae of New Guinea VII. Blumea 26(1): 237 [secondary reference]

Jacobs, S.W.L. & Pickard, J. (1981), Plants of New South Wales: 76 [secondary reference]

Stanley, T.D. in Stanley, T.D. & Ross, E.M. (1986), Asteraceae. Flora of South-eastern Queensland 2: 572, Fig. 80I [secondary reference]

nomenclatural synonym: Gynura crepidioides Benth. legitimate common name: Thickhead [n/a]

Harden, G.J. in Harden, G.J. (ed.) (1992), Crassoceplalum. Flora of New South Wales 3: 297 [secondary reference]

common name: Thickhead [n/a]

Du Puy, D.J., Telford, I.R.H. & Orchard, A.E. (1993), Asteraceae. Flora of Australia 50: 426 [secondary reference]

nomenclatural synonym: Gynura crepidioides Benth. legitimate

Green, P.S. in Wilson, A.J.G. (ed.) (1994), Norfolk Island & Lord Howe Island. Flora of Australia 49: 397 APC [secondary reference]

nomenclatural synonym: Gynura crepidioides Benth. legitimate

• APC Dist.: ChI (naturalised), Qld (naturalised), NSW (naturalised), NI (naturalised)

Hyland, B.P.M., Gray, B. & Elick, R.W. in Cooper, W.E. & Cooper, W.T. (1994), Appendix I: Provisional Species List. Fruits of the Rainforest: 302 [secondary reference]

Hyland, B.P.M., Whiffin, T.P., Christophel, D.C., Gray, B., Elick, R.W. & Ford, A.J. (1999), Australian tropical rain forest trees and shrubs. Australian tropical rain forest trees and shrubs: 57 [secondary reference]

Hyland, B.P.M., Whiffin, T.P., Christophel, D.C., Gray, B. & Elick, R.W. (2003), Australian tropical rain forest plants. Trees, Shrubs and Vines: Code 3439 [secondary reference]

Cooper, W.E. & Cooper, W.T. (2004), Fruits of the Australian Tropical Rainforest: 81 [secondary reference]

nomenclatural synonym: Gynura crepidioides Benth. legitimate common name: Thickhead [n/a]

Thompson, I.R. (22 November 2006), A taxonomic treatment of tribe Senecioneae (Asteraceae) in Australia. Muelleria 24: 102-103 [secondary reference]

common name: Thickhead [n/a]

Thompson, I.R. in Wilson, A.J.G. (ed.) (2015), Crassocephalum. Flora of Australia 37: 311-312, Fig. 37D-F, map [secondary reference]

nomenclatural synonym: Gynura crepidioides Benth. legitimate common name: Thickhead [n/a]

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