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  1. Yuri Gurevich & Harry R. Lewis (1984). The Word Problem for Cancellation Semigroups with Zero. Journal of Symbolic Logic 49 (1):184-191.
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  2. Harry R. Lewis (1983). Review: Michael R. Garey, David S. Johnson, Computers and Intractability. A Guide to the Theory of NP-Completeness. [REVIEW] Journal of Symbolic Logic 48 (2):498-500.
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  3. Stål O. Aanderaa, Egon Börger & Harry R. Lewis (1982). Conservative Reduction Classes of Krom Formulas. Journal of Symbolic Logic 47 (1):110-130.
    A Krom formula of pure quantification theory is a formula in conjunctive normal form such that each conjunct is a disjunction of at most two atomic formulas or negations of atomic formulas. Every class of Krom formulas that is determined by the form of their quantifier prefixes and which is known to have an unsolvable decision problem for satisfiability is here shown to be a conservative reduction class. Therefore both the general satisfiability problem, and the problem of satisfiability in finite (...)
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  4. Harry R. Lewis (1979). Unsolvable Classes of Quantificational Formulas. Addison-Wesley Pub. Co..
     
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  5. Harry R. Lewis (1976). Krom Formulas with One Dyadic Predicate Letter. Journal of Symbolic Logic 41 (2):341-362.
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  6. Warren D. Goldfarb & Harry R. Lewis (1975). Skolem Reduction Classes. Journal of Symbolic Logic 40 (1):62-68.
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  7. Harry R. Lewis & Warren D. Goldfarb (1975). Skolem Reduction Classes. Journal of Symbolic Logic 40 (March):62-68.
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  8. Stal O. Aanderaa & Harry R. Lewis (1974). Linear Sampling and the |Forall |Exists |Forall Case of the Decision Problem. Journal of Symbolic Logic 39 (3):519 - 548.
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  9. Stål O. Aanderaa & Harry R. Lewis (1973). Prefix Classes of Krom Formulas. Journal of Symbolic Logic 38 (4):628-642.
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  10. Harry R. Lewis & Warren D. Goldfarb (1973). The Decision Problem for Formulas with a Small Number of Atomic Subformulas. Journal of Symbolic Logic 38 (3):471-480.
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