Donald M. Kaplan

Some Completeness Results in the Mathematical Theory of Computation

Donald M. Kaplan, 1968, JACM.

Regular Expressions and the Equivalence of Programs

Donald M. Kaplan, D. Kaplan, 1969, J. Comput. Syst. Sci..

Recursion induction applied to generalized flowcharts

Donald M. Kaplan, D. Kaplan, 1969, ACM '69.