Curtis, W. (1793), Flora Londinensis 2(6, 67): pl. 168 [pl. 55 of fascicle 6] [tax. nov.]

• Type: (not cited).

Black, J.M. (1916), Additions to the Flora of South Australia. No 9. Transactions and proceedings of the Royal Society of South Australia 40: 76 [secondary reference]

Black, J.M. (1929), Bignoniaceae - Compositae. Flora of South Australia 4: 653, Fig. 312 [secondary reference]

common name: Slender Thistle [n/a]

Ewart, A.J. (1931), Flora of Victoria: 1186 [taxonomic synonym]

taxonomic synonym of: Carduus pycnocephalus L. legitimate

Black, J.M. & Robertson, E.L. (1957), Flora of South Australia Edn. 2, 4: 934, Fig. 1239 [secondary reference]

common name: Slender Thistle [n/a]

Beadle, N.C.W., Evans, O.D. & Carolin, R.C. (1962), Handbook of the Vascular Plants of the Sydney District and Blue Mountains: 379 [secondary reference]

common name: Winged Slender Thistle [n/a]

Curtis, W.M. (1963), Angiospermae: Lythraceae to Epacridaceae. The Student's Flora of Tasmania 2: 376 [secondary reference]

common name: Winged Slender Thistle [n/a]

Kazmi, S.M.A. (1964), Revision der Gattung Carduus (Compositae). Mitteilungen der Botanischen Staatssammlung Munchen 5: 447-448 [secondary reference]

Burbidge, N.T. & Gray, M. (1970), Flora of the Australian Capital Territory: 392 [secondary reference]

common name: Slender Thistle [n/a]

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. & Leigh, J.H. (1981), Plants of Western New South Wales: 724 [secondary reference]

common name: Sheep Thistle [n/a] common name: Italian Thistle [n/a] common name: Slender-flowered Thistle [n/a] common name: Winged Slender Thistle [n/a]

Jacobs, S.W.L. & Pickard, J. (1981), Plants of New South Wales: 74 [secondary reference]

Green, J.W. (1985), Census of the Vascular Plants of Western Australia Edn. 2: 164 [secondary reference]

Gray, M. & Michael, P.W. (1986), List of plants collected at the old Flemington Saleyards, Sydney, New South Wales. Plant Protection Quarterly 1(4): 137 [secondary reference]

common name: Slender thistle [n/a]

Stanley, T.D. in Stanley, T.D. & Ross, E.M. (1986), Asteraceae. Flora of South-eastern Queensland 2: 581 [secondary reference]

common name: Slender Thistle [n/a]

Lander, N.S. in Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. & Macfarlane, T.D. (1987), Asteraceae. Flora of the Perth Region 2: 665 [secondary reference]

common name: Winged Slender Thistle [n/a] common name: Sheep Thistle [n/a]

Murray, L. in Harden, G.J. (ed.) (1992), Carduus. Flora of New South Wales 3: 321-322 [secondary reference]

common name: Winged Slender Thistle [n/a]

Green, P.S. in Wilson, A.J.G. (ed.) (1994), Norfolk Island & Lord Howe Island. Flora of Australia 49: 366-367 [secondary reference]

• APC Dist.: WA (naturalised), SA (naturalised), Qld (naturalised), NSW (naturalised), NI (naturalised), ACT (naturalised), Vic (naturalised), Tas (naturalised)

Jeanes, J.A. in Walsh, N.G. & Entwisle, T.J. (ed.) (1999), Asteraceae. Flora of Victoria 4: 669, 671, Fig. 128g [secondary reference]

pro parte misapplication: Carduus pycnocephalus L. legitimate by Ewart, A.J. (1931), Flora of Victoria: 1186 common name: Winged Slender-thistle [n/a]

Wheeler, J.R., Marchant, N.G. & Lewington, M. (2002), Dicotyledons. Flora of the South West 2: 498 [secondary reference]

common name: Sheep Thistle [n/a] common name: Winged Slender Thistle [n/a]

Council of Heads of Australasian Herbaria (2011), Australian Plant Census: - APC [secondary reference]

• APC Dist.: WA (naturalised), SA (naturalised), Qld (naturalised), NSW (naturalised), NI (naturalised), ACT (naturalised), Vic (naturalised), Tas (naturalised)

Bean, A.R. in Wilson, A.J.G. (ed.) (2015), Asteraceae Subfam. 2. Carduoideae Trib. 1. Cardueae. Flora of Australia 37: 55, map [secondary reference]

common name: Sheep Thistle [n/a] common name: Winged Slender Thistle [n/a] common name: Slender Thistle [n/a]

de Salas, M.F. & Baker, M.L. (2016), A Census of the Vascular Plants of Tasmania, including Macquarie Island: 12 [secondary reference]

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