1. T. Berners-Lee, Y. Chen, L. Chilton, D. Connolly, R. Dhanaraj, J. Hollenbach, A. Lerer, D. Sheets, Tabulator: Exploring and analyzing linked data on the semantic web, in: Proc. 3rd Int. Semantic Web User Interaction Workshop, 2006.
2. A. Singhal, Introducing the Knowledge Graph: things, not strings, in: Official Google Blog, 2012, https://googleblog.blogspot.co.uk/2012/05/introducing-knowledge-graph-things-not.html.
3. I.F. Cruz, A.O. Mendelzon, P.T. Wood, A graphical query language supporting recursion, in: Proc. ACM SIGMOD, 1987, pp. 323–330.
4. D. Calvanese, G.D. Giacomo, M. Lenzerini, M.Y. Vardi, Containment of conjunctive regular path queries with inverse, in: Proc. 7th Int. Conf. on Principles of Knowledge Representation and Reasoning, 2000, pp. 176–185.
5. K. Kochut, M. Janik, SPARQLeR: Extended SPARQL for semantic association discovery, in: Proc. 4th European Semantic Web Conference, 2007, pp. 145–159.