Bennett, E.M. (14 November 1972), A revision of the Australian species of Hybanthus Jacquin (Violaceae). Nuytsia 1(3): 239, Fig. 9 (map) [explicit autonym]

Jacobs, S.W.L. & Pickard, J. (1981), Plants of New South Wales: 210 [secondary reference]

Adams, L.G. & George, A.S. in George, A.S. (ed.) (1982), Violaceae. Flora of Australia 8: 106, Map 112 APC [secondary reference]

• APC Dist.: NSW, Vic

James, T.A. in Harden, G.J. (ed.) (1990), Violaceae. Flora of New South Wales 1: 440 [secondary reference]

Entwisle, T.J. in Walsh, N.G. & Entwisle, T.J. (ed.) (1996), Violaceae. Flora of Victoria 3: 368, Fig. 75d [secondary reference]

nomenclatural synonym: Ionidium vernonii F.Muell. legitimate common name: Erect Violet [n/a]

James, T.A. in Harden, G.J. (ed.) (2000), Violaceae. Flora of New South Wales Revised Edition 1: 440 [secondary reference]

Forster, P.I. (24 March 2021), Reinstatement of Pigea Ging., an earlier generic name for the spade flowers previously included in Afrohybanthus Flicker (Violaceae). Austrobaileya 11: 32 [nomenclatural synonym]

nomenclatural synonym of: Pigea vernonii (F.Muell.) P.I.Forst. legitimate

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