Composition #1: Ravishankara, MN., Shrivastava, N., Padh, H., Rajani, M. HPTLC method for the estimation of alkaloids of Cinchona officinalis stem bark and its marketed formulations. PLANTA MEDICA, 2001, vol. 67, no. 3, p. 294–296. DOI: 10.1055/s-2001-11995.
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