# Reverse mathematics, Ramsey theorem and mass problem

If we look at reverse mathematics statements as mass problems, considering the class of solutions of an instance, it is known that Weak König's lemma has a maximal instance in the sense that there is an infinite computable binary tree $T$ such that for every path $P$ in the tree and every infinite computable binary tree $U$, $P$ computes a path in $U$.

I heard that it was known not to be the case for Ramsey theorem for pairs, ie for every computable coloring function $f$ over pairs, there is an infinite homogeneous set $H$ and a computable coloring function $g$ over pairs such that $H$ computes no infinite homogeneous set for $g$. But I couldn't find any reference. Does someone know who proved it ?

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