S. Bera, and A. Chakrabarti. 34th Symposium on Theoretical Aspects of Computer Science, STACS 2017, March 8-11, 2017, Hannover, Germany, page 11:1--11:14. (2017)
A. Bolles, M. Grawunder, and J. Jacobi. The Semantic Web: Research and Applications, volume 5021 of Lecture Notes in Computer Science, Springer Berlin Heidelberg, (2008)