Trease and Evans' Pharmacognosy
This encyclopedic reference work on pharmacognosy covers the study of those natural substances, principally plants, that find a use in medicine. Its popularity and longevity stem from the book's balance between classical (crude and powdered drugs' characterization and examination) and modern (phytochemistry and pharmacology) aspects of this branch of science, as well as the editor's recognition in recent years of the growing importance of complementary medicines, including herbal, homeopathic and aromatherapy.
Reference work for pharmaceutical companies
Herbal medicine practitioners