Royal Horticultural Society - Royal Horticultural Society
- 21 nov 2014
- https://www.rhs.org.uk/plants/search-form
- Royal Horticultural Society
University of Maryland Medical Center - UM Medical Center Complementary and Alternative Medicine Guide
- University of Maryland Medical Center
- 27 nov 2014
- http://umm.edu/health/medical/altmed
MedlinePlus Herbs and Supplements - MedlinePlus Herbs and Supplements
- National Institutes of Health
- 2014
- http://www.nlm.nih.gov/medlineplus/druginfo/herb_All.html
