R. W. den Outer

• A provisional determination key to 54 continental African Dichapetalum species, based on anatomical characters of the secondary xylem
• Bark anatomy of some Sarcolaenaceae and Rhopalocarpaceae and their systematic position
• Histological investigations of the secondary phloem of gymnosperms
• Tentative determination key to 600 trees, shrubs and climbers from the Ivory Coast, Africa, mainly based on characters of the living bark, besides rhytidome and the leaf
• The secondary phloem of Amentotaxus
• Wood anatomy of some Sarcolaenaceae and Rhopalocarpaceae and their systematic position