Poole, Mackworth & Goebel 1998 , pp. 199-233, Nilsson 1998 , chpt. ~17.1-17.4 ^ a b Representing categories and relations: Semantic networks , description logics , inheritance (including frames and scripts ): Russell & Norvig 2003 , pp. 349-354, Poole, Mackworth & Goebel 1998 , pp. 174-177, Luger & Stubblefield 2004 , pp. 248-258, Nilsson