OBJ2 plus logic programming based on Horn logic with equality.
"EQLog: Equality, Types and Generic Modules for Logic Programming", J. Goguen et al in Functional and Logic Programming, D. DeGroot et al eds, pp.295-363, P-H 1986.
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Nearby terms: EPSS « EqL « EQLOG « EQLog » Eqn » equals » equational logic