Order:
  1.  15
    Decidable classes of number‐theoretic sentences.I. J. Heath - 1969 - Mathematical Logic Quarterly 15 (26‐29):411-420.
  2.  22
    Decidable classes of number‐theoretic sentences.I. J. Heath - 1969 - Mathematical Logic Quarterly 15 (26-29):411-420.
  3.  19
    Omitting the replacement schema in recursive arithmetic.I. J. Heath - 1967 - Notre Dame Journal of Formal Logic 8 (3):234-238.