For Verbenaceae
Atkins In Kadereit, J.W. 2004. The families and genera of vascular plants. VII. Flowering plants – Dicotyledons – Lamiales (except Acanthaceae including Avicenniaceae). Springer, Berlin. 478 pp.
Marx, H.E., N. O’Leary, Y.-W. Yuan, P. Lu-Irving, D.C. Tank, M.E. Múlgura, and R.G. Olmstead. 2010. A molecular phylogeny and classification of Verbenaceae. Amer. J. Bot. 97: 1647-1663.
Yuan, Y.-W., and R.G. Olmstead. 2008. A species-level phylogenetic study of the Verbena complex (Verbenaceae) indicates two independent intergeneric chloroplast transfers. Molec. Phylogen. & Evol. 48: 23-33.