Computing answers in default logic. - Ramiro A. de T. Guerreiro; Andrea Silva; Marco Antonio Casanova (TAI, 1989)

Logic Programming with General Clauses and Defaults Based on Model Elimination. - Marco A. Casanova; Ramiro A. de T. Guerreiro; Andrea Silva (IJCAI, 1989)

Computing Answers to Logic Programs with Weak Model Elimination. - Marco A. Casanova; Ramiro A. de T. Guerreiro; Andrea Silva (NACLP, 1989)

On the Complexity of Monotonic Inheritance with Roles. - Ramiro A. de T. Guerreiro; Andrea S. Hemerly; Yoav Shoham (AAAI, 1990)

Contributions to a Proof Theory for Generic Defaults. - Ramiro A. de T. Guerreiro; Marco A. Casanova; Andrea S. Hemerly (ECAI, 1990)

Explaining SLDNF resolution with non-normal defaults. - Marco A. Casanova; Andrea S. Hemerly; Ramiro A. de T. Guerreiro (IBM J. Res. Dev., 1992)

STORK and PENGUIN: Logic programming systems using general clauses and defaults. - Ramiro A. de T. Guerreiro; Andrea S. Hemerly; Marco A. Casanova (IBM J. Res. Dev., 1992)