Table:
text: 1994 Australian Touring Car season
Race Calendar
Race Calendar
Date_ Series Circuit City_State Winner Team
10 Apr ATCC Round 4 Phillip Island Grand Prix Circuit Phillip Island , Victoria Glenn Seton Glenn Seton Racing
17 Apr AMC Round 1 Eastern Creek Raceway Sydney , New South Wales Tony Longhurst Logamo Racing
24 Apr ATCC Round 5 Lakeside International Raceway Brisbane , Queensland Larry Perkins Castrol Perkins Racing
15 May ATCC Round 6 Winton Motor Raceway Benalla , Victoria Glenn Seton Glenn Seton Racing
22 May AMC Round 2 Phillip Island Grand Prix Circuit Phillip Island , Victoria Paul Morris Logamo Racing
5 Jun ATCC Round 7 Eastern Creek Raceway Sydney , New South Wales Peter Brock Holden Racing Team
19 Jun AMC Round 3 Winton Motor Raceway Benalla , Victoria Paul Morris Logamo Racing

Question: What date was a series of ATCC Round 6s on the 1994 Australian Touring Car season racing calendar?