1. Gram: A graph data model and query languages;Amann,1992
2. Graphdb: Modeling and querying graphs in databases;Güting,1994
3. Data cube: A relational aggregation operator generalizing group-by, cross-tab, and sub-total;Gray,1996
4. Graph OLAP: Towards online analytical processing on graphs;Chen,2008
5. A framework for building OLAP cubes on graphs;Ghrab,2015