1. Andersson, N. J., 1855: Om Galapagos-öarnas vegetations. ? Kungl. Svenska Vetenskapsakad. Handl. ? Stockholm.
2. Axelius, B., 1992: Testa patterns in some species ofPhysalis L. and some other genera in the tribeSolaneae (Solanaceae). ? Int. J. Pl. Sci.153: 488?502.
3. Bitter, G., 1921: Zur GattungCacabus Bernh. ? Repert. Spec. Nova Regni Vegit.17: 243?245.
4. Belcher, E., 1843: Narrative of a voyage round the world performed in Her Majesty's Ship Sulphur, during the years 1836?1842. ? London: Henry Colburn.
5. Bentham, G., 1844: The botany of the voyage of H.M.S. Sulphur. ? London: Smith, Elder.