Linnaeus, C. (1 May 1753), Species Plantarum 1: 171 [tax. nov.]

Lammers, T.G. in Kubitzki, K. (ed.) (2007), Campanulaceae. The Families and Genera of Vascular Plants 8: 46 [secondary reference]

Mabberley, D.J. (1 May 2008), Mabberley's Plant-Book Edn. 3: 865 [secondary reference]

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