I am studying Kunen's Set Theory (2011 edition) on my own. I got stuck at the excercise I.9.6 which is:

**Excercise I.9.6.** Derive the axiom of replacement from lemma I.9.5.

And the mentioned lemma is this:

**Lemma I.9.5.** For a relation R and a class A, if R is set-like on A, then R* is set-like on A.

Here R* is the transitive closure of R. Also, a relation R is *set-like* on a class A if { x\in A : xRy } is a set for all y\in A.

Help appreciated.