Fields of sets, set functions, set function integrals, and finite additivity. Appling, William D.L. — 1984 International Journal of Mathematics and Mathematical Sciences
A dominated convergence theorem for real-valued summable set functions Appling, William D.L. — 1970 Portugaliae mathematica
Continuity and the subdivision norm infimum function Appling, William D.L. — 1976 Portugaliae mathematica
Refinement-Unbounded Set Functions and Absolute Continuity. William D.L. Appling — 1966 Mathematische Zeitschrift
An Extended Notion of Refinement-Unboundedness. William D.L. Appling — 1968 Monatshefte für Mathematik