Straights Puzzle Book (Str8ts): 200 Easy to Hard (7x7) Puzzles (Adult Brain Games Series): Alzamili, Dr. Khalid: 9798714225741: Amazon.com: Books
Introducing “Sudoku Sequences” or “Sudoku Straights”
Str8ts - 200 Easy to Normal Puzzles 6x6 (Volume 3): Opaternyi, Artem: 9798572404128: Amazon.com: Books
Straights Adult Puzzle Book: 1000 Easy to Hard Str8ts (9x9) Puzzles (The Big Books of Logic Puzzles Series): Alzamili, Dr. Khalid: 9798526846813: Amazon.com: Books
Str8ts - 200 Easy to Normal Puzzles 5x5 (Volume 1): Opaternyi, Artem: 9798572403947: Amazon.com: Books