1. Al-Shebhaz, I. A., 1991: The genera ofBoraginaceae in the Southeastern United States. ? J. Arnold Arbor., Suppl. Ser.1: 1?169.
2. Altamura, L., Colasante, M., D'Amato, G., 1986: Numeri cromosomici per la Flora Italiana: 1022?1036. ? Inform. Bot. Ital.16: 261?270.
3. Arano, H., Saito, H., 1980: Cytological studies in familyUmbelliferae. V. Karyotypes of seven species in subtribeSeselinae. ? Kromosomo2: 471?480.
4. Baillon, H. E., 1890: Histoire des plantes.10. Monographie des Asclépiadacées, Convolvulacées, Polémoniacées et Boraginacées. ? Paris: Hachette.
5. Bentham, G., 1876:Boragineae. ? InBentham, G., Hooker, J. D., (Eds): Genera plantarum,2. ? London: Reeve; Norgate: Williams.