1. Solving a linear diophantine equation with lower and upper bounds on the variables;Aardal,1998
2. An integer programming model for the sudoku problem;Bartlett;J. Online Mathe. Appl.,2008
3. On the number of sudoku squares;Berend;Discr. Mathe.,2018
4. Opt Art: From Mathematical Optimization to Visual Design;Bosch,2019
5. The complexity of theorem-proving procedures;Cook,1971