BioStor
 | XLVIII.—On the comparative carpical structure of the Ehretiaceæ and Cordiaceæ John Miers (1869) Annals And Magazine of Natural History 3: 383-388 |
 | Studies in the Boraginaceae, XVIII. Boraginaceae of the southern West Indies I M Johnston (1949) Journal of the Arnold Arboretum 30: 111-138 |
 | How Rich is the Flora of Brazilian Cerrados? A A J F Castro, F R Martins et al. (1999) Annals of the Missouri Botanical Garden 86: 192-224 |