Literature

• Axelrod, F.S. 2015. A Systematic Vademecum to the Vascular Plants of Sint Eustatius. 179 pp.
• Boldingh, I. 1909. The flora of the Dutch West Indian Islands St. Eustatius, Saba and St. Martin. 321 pp. E.j. Brill., Leiden.
• Boom, B.M. 2008. Flowering Plants. Plants & Lichens of St. Eustatius The New York Botanical Garden. [link]
• Howard, R.A. 1989. Dicotyledoneae - Part 3. In: Flora of the Lesser Antilles, Leeward and Windward Islands. 6: 658. Arnold Arboretum, Harvard University, Jamaica Plain, Massachusetts.
• Mori, S.A., Gracie, C.A. 2007. Flowering Plants. Plants and Lichens of Saba Virtual Herbarium of The New York Botanical Garden. [link]
• Posthouwer, C., Verheijden, T.M.S., Andel, T.R. van 2016. A Rapid Sustainability Assessment of Wild Plant Extraction on the Dutch Caribbean Island of St. Eustatius. Economic Botany 20(10): 1-12.
• Proosdij, A.S.J. van 2012. Arnoldo's Zakflora: Wat in het wild groeit en bloeit op Aruba, Bonaire en Curaçao. 318 pp. Walburg Pers, Zutphen.
• Rojer, A. 1997. Biological Inventory of Saba. 87 pp. CARMABI Foundation, Curaçao.
• Rojer, A. 1997. Biological inventory of Sint Eustatius. CARMABI Foundation, Curaçao.
• Rojer, A. 1997. Biological inventory of St. Maarten. 102 pp. CARMABI Foundation, Curaçao.
• The Plant List 2013. The Plant List version 1.1. [link]
• WCSP 2017. World Checklist of Selected Plant Families. Facilitated by the Royal Botanic Gardens, Kew. [link]

Literature references linked to higher taxa

• Encyclopedia of Life. [link] (Verbenaceae)