Composition #2: Asano, N., Yokoyama, K., Sakurai, M., Ikeda, K., Kizu, H., Kato, A., Arisawa, M., Hoke, D., Drager, B., Watson, AA., Nash, RJ. Dihydroxynortropane alkaloids from calystegine-producing plants. phytochemistry, 2001, vol. 57, no. 5, p. 721–726. DOI: 10.1016/S0031-9422(01)00131-5.
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