fredthebear: Note the tournament Parnu 1971 so as not to confuse it with other Bronstein - Keres games.
The original and only rated game that David Bronstein played as White in this 4.f4 line. Paul Keres inserted 3...Nc6 before 4...Nxe4. Typically, 3...Nxe4 is played in the Blanel Gambit. There are many examples of this 3...Nxe4 approach in the database.
David Bronstein did not hesitate to play gambits, more so in casual games. However, Bronstein rarely played the Bishop's Opening nor the Vienna Game. He typically played 1.e4 e5 2.Nf3 or 2.f4.
Bronstein's book "200 Open Games" includes an example of Blanel's Gambit 3...Nxe4 in Chapter 2 The Bishop's Attack, page 5. Chapter 5 The Vienna Game does not mention Bronstein's 4.f4: https://www.amazon.com/200-Open-Gam...
Thus, the Vienna Game: Stanley Variation. Bronstein Gambit (C23) is rather obscure. This 4.f4 Bronstein gambit is not mentioned on Bronstein's Wikipedia page: https://en.wikipedia.org/wiki/David...
If you want details of the Bishop's Opening or the Vienna Game, I suggest the books written by Gary Lane.
Bronstein's Gambit 4.f4 by Transposition:
Nagy (2175) vs. Raetsch (2140)
Budapest 1999 · Bishop's opening, Greco gambit (C24) · 1-0
Nagy, Karoly (2175)
Raetsch, Kurt (2140)
Event: Budapest Spring op 15th
Round: 6 Date: 03/22/1999
ECO: C24 Score: 1-0
1.e4 e5 2.Bc4 Nf6 3.f4 Nxe4 4.Nc3 Nxc3 5.dxc3 c6 6.Qe2 d5 7.Qxe5+ Be7 8.Bd3 O-O 9.Qh5 g6 10.Qf3 Re8 11.Ne2 Bc5 12.Bd2 Nd7 13.O-O-O b5 14.Nd4 Qb6 15.Rhe1 Bb7 16.Qh3 Nf8 17.f5 b4 18.Nb3 a5 19.Nxc5 Qxc5 20.Qh6 Qd6 21.Kb1 c5 22.Bg5 Nd7 23.Bb5 Bc6 24.Bxc6 Qxc6 25.c4 d4 26.Rf1 a4 27.f6
Comp Dark Thought vs. Vreeken (2130)
The Hague 1996 · Bishop's opening, Greco gambit (C24) · 1-0
Comp Dark Thought,
Vreeken, Corry (2130)
Event: The Hague AEGON
Site: The Hague
Round: 6 Date: 04/17/1996
ECO: C24 Score: 1-0
1.e4 e5 2.Bc4 Nf6 3.f4 Nxe4 4.Nc3 Nxc3 5.dxc3 Be7 6.fxe5 c6 7.Qg4 g6 8.Qf3 f5 9.Be3 Qc7 10.O-O-O a6 11.Qf4 b5 12.Bf7+ Kd8 13.Qh6 c5 14.Nf3 Bb7 15.Qg7 Rf8 16.Bg5 Rxf7 17.Qg8+ Rf8 18.Qxf8#