https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4834991/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5311041/
http://jnm.snmjournals.org/content/58/8/1307.long
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5473955/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6278855/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5980520/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6455066/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7051207/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7383012/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4478035/