Table:
text: 1979 British Formula One season
Races
Races
Round Name_ Circuit Date_ Winning_driver Winning_car
1 Belgian Cup Zolder April 1 Dave Kennedy Wolf WR4
2 International Gold Cup Oulton Park April 13 Dave Kennedy Wolf WR4
3 Race of Champions Brands Hatch April 15 Guy Edwards Fittipaldi F5A
4 Sun Trophy Mallory Park May 7 Rupert Keegan Arrows A1
5 Anglia TV Trophy Snetterton May 20 Rupert Keegan Arrows A1
6 Rivet Supply Trophy Thruxton May 28 Emilio de Villota Lotus 78
7 International Whitsuntide Race Zandvoort June 4 Emilio de Villota Lotus 78
8 Donington Formula 1 Trophy Donington Park June 24 Rupert Keegan Arrows A1

Question: Which circuit did Guy Edwards win in the 1979 British Formula 1 season?