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  1. Larry Wos, Dolph Ulrich & Branden Fitelson, Vanquishing the XCB Question: The Methodological Discovery of the Last Shortest Single Axiom for the Equivalential Calculus.
    detail a question that, for a quarter of a century, remained open despite intense study by various researchers. Is the formula XC B = e(x e(e(e( ) e( )) z)) a single axiom for the classical equivalential calculus when the rules of inference consist..
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  2. Dolph Ulrich (2012). A Single Axiom for Relevant Implication. Bulletin of the Section of Logic 41 (1/2):13-16.
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  3. Dolph Ulrich (2009). On Two Open Questions Concerning the Implicational Fragment of R-Mingle. Bulletin of the Section of Logic 38 (1/2):1-4.
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  4. Dolph Ulrich (2005). D-Complete Axioms for the Classical Equivalential Calculus. Bulletin of the Section of Logic 34 (3):135-142.
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  5. Dolph Ulrich (1996). The Shortest Possible Length of the Longest Implicational Axiom. Journal of Philosophical Logic 25 (1):101 - 108.
    A four-valued matrix is presented which validates all theorems of the implicational fragment, IF, of the classical sentential calculus in which at most two distinct sentence letters occur. The Wajsberg/Diamond-McKinsley Theorem for IF follows as a corollary: every complete set of axioms (with substitution and detachment as rules) must include at least one containing occurrences of three or more distinct sentence letters. Additionally, the matrix validates all IF theses built from nine or fewer occurrences of connectives and letters. So the (...)
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  6. Dolph Ulrich (1994). On the Independence of B From I, C, W, K 1′, and Karpenko's Formula X. Bulletin of the Section of Logic 23:96-97.
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  7. Dolph Ulrich (1992). On the Incompleteness of a Descending Chain of Extensions of Implicational S5. Mathematical Logic Quarterly 38 (1):321-323.
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  8. Dolph Ulrich (1987). A Five-Valued Model of the $E$-$P$-$Q$-Theses. Notre Dame Journal of Formal Logic 29 (1):137-138.
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  9. Dolph Ulrich (1986). Review: Donald Nute, Essential Formal Semantics. [REVIEW] Journal of Symbolic Logic 51 (1):252-253.
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  10. Dolph Ulrich (1985). A Descending Chain of Incomplete Extensions of Implicational S 5. Mathematical Logic Quarterly 31 (13):201-208.
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  11. Dolph Ulrich (1984). Answer to a Question Suggested by Schumm. Zeitschrift fur mathematische Logik und Grundlagen der Mathematik 30 (25):385-387.
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  12. Dolph Ulrich (1983). Models of Three-Valued Calculi in Implicational S5. Bulletin of the Section of Logic 12 (2):73-75.
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  13. Dolph Ulrich (1983). The Finite Model Property and Recursive Bounds on the Size of Countermodels. Journal of Philosophical Logic 12 (4):477 - 480.
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  14. Dolph Ulrich (1982). Answer to a Question Raised by Harrop. Bulletin of the Section of Logic 11 (3/4):140-141.
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  15. Dolph Ulrich (1981). ${\Rm RMLC}$: Solution to a Problem Left Open by Lemmon. Notre Dame Journal of Formal Logic 22 (2):187-189.
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  16. Dolph Ulrich (1981). Strict Implication in A Sequence of Extensions of S4. Mathematical Logic Quarterly 27 (13‐14):201-212.
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  17. Dolph Ulrich (1978). Semantics for ${\Rm S}4.1.2$. Notre Dame Journal of Formal Logic 19 (3):461-464.
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  18. Dolph Ulrich (1976). On a Modal System of R. A. Bull's. Notre Dame Journal of Formal Logic 17 (3):479-480.
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  19. Dolph Ulrich (1976). Generalization of a Result of Pahi's. Mathematical Logic Quarterly 22 (1):437-438.
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  20. Dolph Ulrich (1976). On a Property of Matrices for Subsystems of IC+. Mathematical Logic Quarterly 22 (1):193-194.
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  21. Dolph Ulrich (1975). Review: R. Harrop, H. Arnold Schmidt, K. Schutte, H.-J. Thiele, Some Forms of Models of Propositional Calculi; Ronald Harrop, On the Equivalence for Non-Derivability Testing of Finite Smiley Models and Finite Modified Smiley Models. [REVIEW] Journal of Symbolic Logic 40 (2):251-251.
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  22. Dolph Ulrich (1975). Review: Timothy Smiley, The Independence of Connectives. [REVIEW] Journal of Symbolic Logic 40 (2):250-251.
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  23. Dolph Ulrich (1974). Erratum: ``Some Results Concerning Finite Models for Sentential Calculi''. Notre Dame Journal of Formal Logic 15 (4):648-648.
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  24. Dolph Ulrich (1972). Some Results Concerning Finite Models for Sentential Calculi. Notre Dame Journal of Formal Logic 13 (3):363-368.
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