Aaron P. Davis, Rafael Govaerts, Diane M. Bridson and Piet Stoffelen. An annotated taxonomic conspectus of the genus Coffea (Rubiaceae), Botanical Journal of the Linnean Society, 2006, 152, 465–512.
Bridson D., 1987. Nomenclatural notes on Psilanthus, including Coffea sect. Paracoffea (Rubiaceae tribe Coffeeae). Kew Bulletin, 42, 817-859.
Sivarajan et. al., Bot. Bull. Acad. Sin. 33: 209. 1992