Problems in Acceptance Testing of Digital Computers - Paul Brock; Sibyl Rock (J. ACM, 1954)

Approach Spaces, Limit Tower Spaces, and Probabilistic Convergence Spaces. - Paul Brock; D. C. Kent (Appl. Categorical Struct., 1997)

On Convergence Approach Spaces. - Paul Brock; Darrell Kent (Appl. Categorical Struct., 1998)