A. Buchau, W. Rucker, U. Wössner, and M. Becker. COMPEL : the International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 28 (4):
948-963(2009)
M. Gärtner, U. Hahn, and S. Hermann. Proceedings of the Eleventh International Conference on Language Resources and Evaluation (LREC 2018), European Language Resources Association (ELRA), (2018)