1. https://www.researchandmarkets.com/reports/5140237/nuclear-medicine-radioisotope-global-accessed. Accessed April 2021
2. https://world-nuclear.org/information-library/non-power-nuclear-applications/radioisotopes-research/radioisotopes-in-medicine.aspx. Accessed April 2021
3. https://www.nti.org/analysis/articles/cns-global-incidents-and-trafficking-database. Accessed Feb 2021
4. https://www.www.iaea.org/nuclear-security/incident-and-trafficking-database. Accessed March 2021
5. International Atomic Energy Agency (2005) Categorization of radioactive sources. IAEA Safety Standards Series No. RS-G-1.9. IAEA, Vienna, p 70