Roger Olson and John Frame have at least one thing in common: they both make sweeping claims about Augustine without offering a single citation to back it up.
In his book Against Calvinism Olson references Augustine four times (24, 104, 152, 189), usually to make some variation of this assertion:
Some of its [Calvinism’s] crucial tenets cannot be found before the church father Augustine in the fifth century (24).
He later repeats this claim regarding limited atonement (152) and unconditional election (189). In all four cases he doesn’t offer a single footnote, nor even a single reference to secondary literature, some study of “the first four centuries,” perhaps. Not one. I guess we’re supposed to take his word for it as some expert on patristics and medieval theology?
Olson is certainly capable of citing sources when he wishes. He quotes Calvin, Boettner, Sproul, Piper, and others extensively in his endnotes.
Perhaps Olson is right about Augustine and “the first four centuries.” If so, it should be simple enough to demonstrate that to the reader, rather than to merely assert it.