FDCA § 201(p)(1) https://www.fda.gov/RegulatoryInformation/Legislation/FederalFoodDrugandCosmeticActFDCAct/FDCActChaptersIandIIShortTitleandDefinitions/ucm086297.htm ↩
"Guidance for FDA Staff and Industry: Marketed Unapproved Drugs — Compliance Policy Guide" (PDF). U.S. FDA. June 2006. Retrieved 2009-07-12. https://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM070290.pdf ↩