1. 1) Matsuhama M., Saito R., Miyazaki S., Chem. Pharm. Bull., 68, 1034–1048 (2020).
2. 2) The United States Pharmacopeial Convention, “USP(232) Elemental Impurities-Limits. Forum,” Vol. 42, 2017, pp. 8065–8069.
3. 3) The United States Pharmacopeial Convention, “USP(233) Elemental Impurities-Procedures. Second Supplement,” Vol. 38, 2015, pp. 1–5.
4. 4) “European Pharmacopeia 10th edition,” chapter 2.4.20, 2019, pp. 144–147.
5. 5) “Supplement II to the Jpapanese Pharmcopoeia 17th edition,” chapter 2.66, 2019, pp. 2893–2896.