Nuel Belnap (1930 – present) Participations: گسترشها Entailment: The Logic of Relevance and Necessity Entailment: The Logic of Relevance and Necessity 1992 author Nuel Belnap author Alan Ross Anderson Entailment: The Logic of Relevance and Necessity Entailment: The Logic of Relevance and Necessity 1975 author Nuel Belnap author Alan Ross Anderson