Killer Sudoku, Difficulty 3

Puzzle 7158 May 7 May 2013
Puzzle 7168 May 9 May 2013
Puzzle 7178 May 11 May 2013
Puzzle 7188 May 13 May 2013
Puzzle 7193 May 14 May 2013
Puzzle 7203 May 16 May 2013
Puzzle 7213 May 18 May 2013
Puzzle 7233 May 22 May 2013
Puzzle 7243 May 24 May 2013
Puzzle 7253 May 26 May 2013
Daily Killer Sudoku