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 ...

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 ...

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