Bach Flower Therapy by Mechthild Scheffer
Dr Edward Bach discovered 38 flower remedies e.g. heather, gentian, elm, crab apple etc. which when taken work on both the emotional and physical level.
This is the most comprehensive book on the Bach Flower Remedies. As well as describing the 38 remedies, it goes into the spiritual and psychological application of the therapy so that both patients and practitioners can gain deeper insight into the underlying concepts.