-
Edward E.
Terrell (Jun 10, 1996), "Revision of
Houstonia (Rubiaceae-
Hedyotideae)",
Systematic Botany Monographs, 48: 1–118, doi:10.2307/25027862, JSTOR 25027862...
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Botanic Gardens Terrell,
Edwards (2001). "Taxonomy of
Stenaria (Rubiaceae:
Hedyotideae), a new
genus including Hedyotis nigricans". Sida. 19 (3): 592. Retrieved...
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genus at
first glance. In habit,
Virectaria strongly resembles African Hedyotideae such as
Otomeria and
Parapentas but it
lacks some
diagnostic features...
-
Edward E.
Terrell (10 June 1996), "Revision of
Houstonia (Rubiaceae-
Hedyotideae)",
Systematic Botany Monographs, 48,
American Society of
Plant Taxonomists:...