Wagner, H., Wagner , H. ., & Wolff , P.. (1977). New natural products and plant drugs with pharmacological , biological or therapeutical activity: Proceedings of the first international congress on medicinal plant research , section A , held at the University of Munich , germany september 6 - 10 , 1976. Springer - verlag.

Wagner, H., H. Wagner , và P. Wolff. New Natural Products and Plant Drugs with Pharmacological , Biological or Therapeutical Activity: Proceedings of the First International Congress on Medicinal Plant Research , Section A , Held at the University of Munich , Germany September 6 - 10 , 1976. New York: Springer - verlag, 1977.

Wagner, H., et al. New Natural Products and Plant Drugs with Pharmacological , Biological or Therapeutical Activity: Proceedings of the First International Congress on Medicinal Plant Research , Section A , Held at the University of Munich , Germany September 6 - 10 , 1976. Springer - verlag, 1977.