Akçin, Öznur E., and R. Binzet. “The Micromorphological and Anatomical Properties of <i>Onosma angustissimum</i> Hausskn. & Bornm. and <i>O. cassium</I> Boiss. (Boraginaceae)”. Bangladesh Journal of Plant Taxonomy, vol. 17, no. 1, June 2010, pp. 1-8, doi:10.3329/bjpt.v17i1.5386.