APA (7th ed.) Citation

Chua, S. L. (2009). Contest problems of world sudoku championships. Anvil Pub.

Chicago Style (17th ed.) Citation

Chua, Simon L. Contest Problems of World Sudoku Championships. Pasig City: Anvil Pub, 2009.

MLA (9th ed.) Citation

Chua, Simon L. Contest Problems of World Sudoku Championships. Anvil Pub, 2009.