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2. Prager, R.H., et al, Aust., J., Chem., 1962, 15, 301 (Evodine)
3. Sidyakin, G.P., et al, Dokl., Akad., Nauk SSSR, 1962, 19, 39 (isol, struct, uv, ir)
4. Dreyer, D.L., Phytochemistry, 1969, 8, 1013 (isol, uv, pmr, struct, deriv)
5. Dreyer, D.L., J., Org., Chem., 1970, 35, 2420 (isol, uv, pmr, struct, deriv)