Killer Sudoku, Difficulty 3

Puzzle 7673 Aug 18 August 2013
Puzzle 7683 Aug 20 August 2013
Puzzle 7693 Aug 22 August 2013
Puzzle 7703 Aug 24 August 2013
Puzzle 7713 Aug 26 August 2013
Puzzle 7723 Aug 28 August 2013
Puzzle 7733 Aug 30 August 2013
Puzzle 7748 Sep 2 September 2013
Puzzle 7758 Sep 4 September 2013
Puzzle 7768 Sep 6 September 2013
Daily Killer Sudoku