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2. a.ICH Guidelines, Q3A (R), Impurities in New Drug Substances, The quality guidelines for Active Pharmaceutical Ingredients related to impurities according to the International Conference of Horminization, February, 2002.
3. bICH Guidelines, Q3B (R) Impurities in New Drug Products, The quality guidelines for Active Pharmaceutical Ingredients related to impurities according to the International Conference of Horminization, February, 2002.
4. cInternational Conferences on Harmonizations, Impurities guidelines for residual solvents. Q3(c), Federal Register, 1997, 62, (247),67377.