Many-sorted elementary equivalence. - Daniel Dzierzgowski (Notre Dame J. Formal Log., 1988)

Intuitionistic typical ambiguity. - Daniel Dzierzgowski (Arch. Math. Log., 1992)

Typical Ambiguity and Elementary Equivalence. - Daniel Dzierzgowski (Math. Log. Q., 1993)

Models of Intuitionistic TT and NF. - Daniel Dzierzgowski (J. Symb. Log., 1995)

Constants in Kripke Models for Intuitionistic Logic. - Daniel Dzierzgowski (Math. Log. Q., 1995)

Finite Sets and Natural Numbers in Intuitionistic TT. - Daniel Dzierzgowski (Notre Dame J. Formal Log., 1996)

Finite Sets and Natural Numbers in Intuitionistic TT Without Extensionality. - Daniel Dzierzgowski (Stud Logica, 1998)

Fixed-points of Set-continuous Operators. - Daniel Dzierzgowski; Olivier Esser; Roland Hinnion (Math. Log. Q., 2000)