The following article presents the KG-OLAP framework:
Knowledge Graph OLAP: A Multidimensional Model and Query Operations for Contextualized Knowledge Graphs
Christoph Schuetz, Loris Bozzato, Bernd Neumayr, Michael Schrefl, and Luciano Serafini
Semantic Web. 2020. In press.
An online Appendix to that article gives additional information regarding formalization and implementation of the KG-OLAP framework.