Index Holmiensis is a world-covering index to distribution maps of vascular plants that was founded in 1969 by Hans Tralau at the Swedish Museum of Natural History. Scientific publications from all parts of the world are systematically scanned by an international team of specialists. The index gives full bibliographic references to published distribution maps - local, regional or world-wide - of vascular plant taxa from family level and below, but mainly at the species level.
Vol. 10 (Dicotyledoneae Q-S) lists publications containing maps of 19,798 taxa.