@Inproceedings{RodríguezPenabad01,
author = {Penabad, M. R. and Brisaboa, N. R. and Param√°, J. R. and Decker, H.},
title = {A general procedure to test containment of conjuctive queries},
booktitle = {Proceedings of the 14th International Conference On Applications of Prolog (INAP'01)},
address = {Tokio},
year = {2001},
pages = {1-10}
}