@inproceedings{DL-2016-obda-beyond-ql,
   title    = {Virtual OBDA over Expressive Ontologies: Rewritings and Approximations},
   year     = {2016},
   author   = {Elena Botoeva and Diego Calvanese and Valerio Santarelli and Domenico Fabio Savo and Alessandro Solimando and Guohui Xiao},
   booktitle = {Proc. of the 29th Int. Workshop on Description Logics (DL 2016)},
   webpdf = {http://www.inf.unibz.it/~ebotoeva/papers/bcsssx-DL-16.pdf},
}