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4. Food and Drug Administration. Guidance for Industry: Regulation of Human Cells Tissues and Cellular and Tissue-Based Products (HCT/Ps). Small Entity Compliance Guide. 2007. https://www.fda.gov/downloads/biologicsbloodvaccines/guidancecomplianceregulatoryinformation/guidances/tissue/ucm062592.pdf.
5. FDA Regulation of Stem-Cell–Based Therapies