1. Substance Abuse and Mental Health Services Administration (SAMHSA) - https://www.samhsa.gov/data/sites/default/files/reports/rpt29393/2019NSDUHFFRPDFWHTML/2019NSDUHFFR1PDFW090120.pdf

2. DrugAbuse.gov - https://www.drugabuse.gov/sites/default/files/CommonlyUsedLAOpioids.pdf

3. Substance Abuse and Mental Health Services Administration (SAMHSA)Substance Abuse and Mental Health Services Administration (SAMHSA) - https://store.samhsa.gov/sites/default/files/SAMHSA_Digital_Download/PEP20-02-01-006_508.pdf