Type Reconstruction in the Presence of Polymorphic Recursion and the Recursive Types

We establish the equivalence of type reconstruction with polymorphic recursion and recursive types is equivalent to regular semi-unification which proves the undecidability of the corresponding type reconstruction problem. We also establish the equivalence of type reconstruction with polymorphic recursion and positive recursive types to a special case of regular semi-unification which we call positive regular semi-unification. The decidability of positive regular semi-unification is an open problem.

Christ versus Krishna : a brief comparison between the chief events, characteristics & mission of the Babe of Bethlehem Judµa and the Babe of Brindabun Mathurapuri : with a concise review of Hindooism, proving its derivation from Christianity / by L.A. Sakes.

http://www.archive.org/details/christversuskris014648mbp