The Definition of GraphDB by Takahiro Inoue.
Yes, GraphDB is also a product name from Sones but in this context it means graph database in the generic sense.
Good thing we don’t have naming issues in the topic map/semantic integration area, would make it hard to find things. 😉
These are some of the best graphics I have ever seen for introducing graphs and their capabilities as data structures.
Definitely worth spending some time with them and forwarding to others.