@article{4:21,author={Vtor Santos Costa and Ashwin Srinivasan and Rui Camacho and Hendrik Blockeel and Bart Demoen and Gerda Janssens and Jan Struyf and Henk Vandecasteele and Wim Van Laer}, Title={Query Transformations for Improving the Efficiency of ILP Systems},journal={Journal of Machine Learning Research},volume={4}, url={http://www.jmlr.org/papers/volume4/botta03a/botta03a.pdf}}