American Academy of Family Physicians » http://www.aafp.org/online/en/home.html
American Academy of Physician Assistants » http://www.aapa.org/
American Association of Nurse Practitioners » http://www.aanp.org
American Diabetes Association
» http://www.diabetes.org/
American Thyroid Association » http://www.thyroid.org/
American Lung Association » http://www.lung.org
American College of Cardiology » http://www.acc.org/
Centers for Disease Control and Prevention » http://www.cdc.gov/
National Institutes of Health » http://www.nih.gov/
United States National Library of Medicine » http://www.nlm.nih.gov/
Clinical Trials » http://clinicaltrials.gov/
Cochrane Primary Health Care Field » https://www.cochranelibrary.com/
PubMed » https://pubmed.ncbi.nlm.nih.gov/