Proof Game in 4 moves
Correct. This next one still appears in the same book, but the author seems to have cited a composer.
A. Buchanan 2004
That would refer to Andrew Buchanan. Answer in white below, and I think I'd stay away after this. Addictive little things these are.
1. e4 Nf6 2. Qh5 Nxe4 3. Qxh7 Nf6 4. Qg8 Nxg8
Oh, and GreenCastleBlock's one is a classic, also a proof game in 4.0. Tibor Orban, Die Schwalbe 1976. I won't give the answer.
I like retros and PGs too. They are quite addictive, except sometimes I have trouble finding them. There are a bunch of retros in that book too, but I just finished working on them so now I'm out.
Anyways, here's another proof game.
For Orban's, there are a bunch of options for 3.0 or 5.0 moves, but the 4.0 solution is unique and intended.
As for your most recent post, I think it's cooked. I see 3 move orders/variations.
I will be posting a bunch of PGs in 4 moves, all from Jeff Coakley's book Winning Chess Puzzles for Kids Volume 2. I'll post a few a day. Here are the first ones.