Variations on Junior Sudoku Logic Puzzles (Vol 1) 
 Chapter 40: Twenty-Seven Difficult Sudoku-6up-UR-D Puzzles (numbers 904-930) 
 
-  Step-by-step instructions for solving  Puzzle 904, (26/36)   Diff: 7/413.4356
 -  Step-by-step instructions for solving  Puzzle 905, (26/36)   Diff: 7/323.5643
 -  Step-by-step instructions for solving  Puzzle 906, (27/36)   Diff: 7/555.2442
 -  Step-by-step instructions for solving  Puzzle 907, (28/36)   Diff: 7/364.4731
 -  Step-by-step instructions for solving  Puzzle 908, (29/36)   Diff: 7/355.3553
 -  Step-by-step instructions for solving  Puzzle 909, (29/36)   Diff: 8/4333.3742
 -  Step-by-step instructions for solving  Puzzle 910, (28/36)   Diff: 9/4.3113.3283
 -  Step-by-step instructions for solving  Puzzle 911, (28/36)   Diff: 9/2.2342.1365
 -  Step-by-step instructions for solving  Puzzle 912, (29/36)   Diff: 9/4.3422.3236
 -  Step-by-step instructions for solving  Puzzle 913, (27/36)   Diff: 10/41.3211.2562
 -  Step-by-step instructions for solving  Puzzle 914, (27/36)   Diff: 10/21.2141.2464
 -  Step-by-step instructions for solving  Puzzle 915, (28/36)   Diff: 10/AA.2132.3672
 -  Step-by-step instructions for solving  Puzzle 916, (28/36)   Diff: 10/41.1123.1267
 -  Step-by-step instructions for solving  Puzzle 917, (28/36)   Diff: 10/22.2322.4245
 -  Step-by-step instructions for solving  Puzzle 918, (28/36)   Diff: 10/22.1122.5571
 -  Step-by-step instructions for solving  Puzzle 919, (29/36)   Diff: 10/44.1A32.3542
 -  Step-by-step instructions for solving  Puzzle 920, (29/36)   Diff: 10/13.1221.3655
 -  Step-by-step instructions for solving  Puzzle 921, (29/36)   Diff: 10/12.3234.3533
 -  Step-by-step instructions for solving  Puzzle 922, (30/36)   Diff: 10/31.3631.4441
 -  Step-by-step instructions for solving  Puzzle 923, (27/36)   Diff: 11/212.3432.2332
 -  Step-by-step instructions for solving  Puzzle 924, (28/36)   Diff: 11/423.1133.2441
 -  Step-by-step instructions for solving  Puzzle 925, (28/36)   Diff: 11/112.5313.2352
 -  Step-by-step instructions for solving  Puzzle 926, (28/36)   Diff: 11/112.2321.3661
 -  Step-by-step instructions for solving  Puzzle 927, (29/36)   Diff: 11/323.4211.5341
 -  Step-by-step instructions for solving  Puzzle 928, (29/36)   Diff: 11/221.1AA3.3474
 -  Step-by-step instructions for solving  Puzzle 929, (30/36)   Diff: 11/233.3323.2432
 -  Step-by-step instructions for solving  Puzzle 930, (30/36)   Diff: 11/122.4131.2365