A survey of the mathematical foundations of Computer Science. Finite automata and regular languages. Stack Acceptors and Context-Free Languages. Turing Machines, recursive and recursively enumerable ...

And Kurt GAPdel worked on the incompleteness theory and recursive function theory. Turing employed the work of both mathematicians to create a conceptual computing machine.

Marvin L. Minsky, Recursive Unsolvability of Post's Problem of "Tag" and other Topics in Theory of Turing Machines, Annals of Mathematics, Vol. 74, No. 3 (Nov., 1961), pp. 437-455 ...