Nuno A. Fonseca Vítor Santos Costa Ricardo Rocha Rui Camacho Fernando M. A. Silva Improving the efficiency of inductive logic programming systems. 189-219 2009 39 Softw., Pract. Exper. 2 http://dx.doi.org/10.1002/spe.896 db/journals/spe/spe39.html#FonsecaCRCS09