Tournament Sudoku Twelve Logic Puzzles (Vol 1) 
 Chapter 3: Twelve Tournament (DiffLev 22-25) Sudoku-12 Puzzles (numbers 1-12) 
 
-  Step-by-step instructions for solving  Puzzle 1, (86/144)   Diff: 22/85.2322.2225.3422.4B44.5993
 -  Step-by-step instructions for solving  Puzzle 2, (94/144)   Diff: 22/98.6542.3342.12BA.4524.6991
 -  Step-by-step instructions for solving  Puzzle 3, (96/144)   Diff: 22/73.2C11.A246.9742.1254.9992
 -  Step-by-step instructions for solving  Puzzle 4, (89/144)   Diff: 23/973.4333.A223.4654.2348.4432
 -  Step-by-step instructions for solving  Puzzle 5, (90/144)   Diff: 23/834.5324.3553.3213.2144.8773
 -  Step-by-step instructions for solving  Puzzle 6, (88/144)   Diff: 24/7445.2C53.4653.3421.2342.3661
 -  Step-by-step instructions for solving  Puzzle 7, (85/144)   Diff: 25/9.5432.1111.B222.211A.1128.9992
 -  Step-by-step instructions for solving  Puzzle 8, (86/144)   Diff: 25/7.43C2.3A23.4542.1212.3346.7572
 -  Step-by-step instructions for solving  Puzzle 9, (91/144)   Diff: 25/5.2233.A211.4444.5253.5777.4541
 -  Step-by-step instructions for solving  Puzzle 10, (91/144)   Diff: 25/4.2A21.1132.2C31.3323.2357.9978
 -  Step-by-step instructions for solving  Puzzle 11, (92/144)   Diff: 25/6.541B.222B.222A.3233.4555.9974
 -  Step-by-step instructions for solving  Puzzle 12, (95/144)   Diff: 25/3.11C1.B2C2.3433.3444.7988.7442