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2. Blair, H.A., Brown, A.L., Definite Clause Programs are Canonical (over a Suitable Domain), Annals of Mathematics in Artificial Intelligence,to appear.
3. Bruynooghe, M., Boulanger, D., Abstract Interpretation for (Constraint) Logic Programming, this volume.
4. Carlson, B., A Characterisation of Logic Programming in Domain Theory, Master Thesis, Department of Computing Science, Uppsala University, 1989.
5. Carlson, B., An Approximation Theory for Constraint Logic Programs, Licentiate Thesis, Department of Computing Science, Uppsala University, 1991.