1. Leclerc, H. Sida Sabdariffa (Hibiscus sabdariffa).
Presse Med 1938; 46: 1060.
2. Leupin, K. Karkade. Pharma Acta Helv 1935; 10: 138.
3. Buogo, G. and D. Picchinenna. Chemical constituents of Roselle hemp.
Ann Chim Appl 1937; 27: 577.
4. Rao, P. S. and T. R. Seshadri. Pigments of the flowers of Hibiscus sabdariffa — Isolation of sabdaretin, a new hydroxyflavene. Proc Indian Acad Sci Ser A 1942; 16: 323.
5. Indovina, R. and G. Capotummino. Chemical investigation of some products which can be obtained from Hibiscus sabdariffa. Boll Studi Informas (Palermo) 1938; 15:1.