Maiden, J.H. (1928), A Critical Revision of the Genus Eucalyptus 7(9): 403 [nom. nov.]

replaced synonym: Eucalyptus angusta Maiden nom. illeg.

• Etymology: "I, therefore, propose the name E. rigidula on account of its narrow, somewhat rigid, leaves."
• Text: "E. angusta is pre-occupied by E. angusta Velenovsky, a fossil species..."

Brooker, M.I.H. (28 December 1979), A revision of the informal series Foecundae Pryor and Johnson of the genus Eucalyptus L'Herit. and notes on variation in the genus. Brunonia 2(1): 139-146 [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg. taxonomic synonym: Eucalyptus uncinata var. major Benth. legitimate

Chippendale, G.M. in Jessop, J.P. (ed.) (1981), Eucalyptus. Flora of Central Australia: 246, Fig. 309 [secondary reference]

Green, J.W. (1985), Census of the Vascular Plants of Western Australia Edn. 2: 127 [secondary reference]

Chippendale, G.M. in George, A.S. (ed.) (27 June 1988), Eucalyptus. Flora of Australia 19: 281, Fig. 83, Map 325 [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg. taxonomic synonym: Eucalyptus uncinata var. major Benth. legitimate pro parte taxonomic synonym: Eucalyptus uncinata var. rostrata Benth. legitimate common name: Stiff-leaved Mallee [n/a]

Robson, Peter J. (1993), Checklist of Australian Trees: alphabetical listings of common and scientific names: - [secondary reference]

common name: Stiff leaved Mallee [n/a]

Brooker, M.I.H. (28 February 2000), A new classification of the genus Eucalyptus L'Her. (Myrtaceae). Australian Systematic Botany 13(1): 109 [secondary reference]

Centre for Plant Biodiversity Research (2006), EUCLID Edn. 3: - [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg. taxonomic synonym: Eucalyptus uncinata var. major Benth. legitimate

Council of Heads of Australasian Herbaria (2006), Australian Plant Census: - APC [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg.

• APC Dist.: WA

Turner, I.M. (2014), Names of extant angiosperm species that are illegitimate homonyms of fossils. Annales Botanici Fennici 51: 317 [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg.

Nicolle, D. & French, M.E. (18 November 2021), A taxonomic revision of the semi-cryptic narrow-leaved mallees (Eucalyptus series Porantherae, Myrtaceae) from southern Australia. Swainsona 35: 125-128, Figs 36-37, 38 (map) [secondary reference]

nomenclatural synonym: Eucalyptus angusta Maiden nom. illeg.

Percy-Bower, J.M. & Parker, C.M. (21 March 2023), Updates to Western Australia’s vascular plant census for 2022. Nuytsia 34: 9 [secondary reference]

taxonomic synonym: Eucalyptus sp. Kalbarri (M.I.H.Brooker 7937) Australian National Herbarium [n/a]

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