user: Question: Which circuit did Winfield Team Nissan win for the Tooheys 1000?
Columns: ['Date', 'Series', 'Circuit', 'City / State', 'Winner', 'Team']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['23 Feb', 'ATCC Round 1', 'Amaroo Park', 'Sydney , New South Wales', 'Mark Skaife', 'Winfield Team Nissan']
SQL:

assistant: SELECT "Circuit" FROM "Table" WHERE "Team" = 'Winfield Team Nissan' AND "Series" = 'Tooheys 1000';