  Autoepistemic logic remains a popular approach to nonmonotonic logic, in part because of its usefulness in providing theoretical foundations for logic programming. For more recent references, see  Marek &amp; Truszczynski 1991,  Moore 1995b,  Marek &amp; Truszczynski 1989,  Konolige 1994,  Antoniou 1997,  Moore 1993,  and  Deneker et al. 2003.