The Optimal Model of a Program with Negation. - Jean-Paul Delahaye; V. Thibau (JELIA, 1990)

A new model semantics for a program with negation. - Jean-Paul Delahaye; V. Thibau (SPLT, 1990)

Programming in Three-valued Logic. - Jean-Paul Delahaye; V. Thibau (Theor. Comput. Sci., 1991)