@article {DBLP:journals/amai/GiannottiGSZ97, title = {Programming with Non-Determinism in Deductive Databases}, journal = {Ann. Math. Artif. Intell.}, volume = {19}, number = {1-2}, year = {1997}, pages = {97-125}, author = {Fosca Giannotti and Sergio Greco and Domenico Sacc{\`a} and Carlo Zaniolo} } @conference {DBLP:conf/dood/GiannottiPSZ91, title = {Non-Determinism in Deductive Databases}, booktitle = {DOOD}, year = {1991}, pages = {129-146}, author = {Fosca Giannotti and Dino Pedreschi and Domenico Sacc{\`a} and Carlo Zaniolo} }