1. Burnett, A.R., Thomson, R.H., 1968. Naturally occurring quinones. Part XV. Biogenesis of the anthraquinones in Rubia tinctorum L. (Madder). J. Chem. Soc. C, 2438–2441.
2. Gomez, K.A., Gomez, A.A., 1984. Statistical Procedures for Agricultural Research. John Wiley, NY, pp. 680.
3. Kinnosuko, O., Takahito, I., Keiko, K., 1991. Madders dye. In: Atsuchi, K. (Ed.), Plant Cell Culture in Japan, CMC. Japan, pp. 138–142.
4. Lea, A.G.H., 1988. HPLC of natural pigments in foodstuffs. In: Macrae, R. (Ed.), HPLC in Food Analysis. Academic Press, London, pp. 277–333.
5. Quantitative analysis of alizarin in tissue cultures of Rubia species by high performance liquid chromatography;Lodhi;Phytochem. Anal.,1994