APA (7th ed.) Citation

Kelsey, K. (1984). A third book of number puzzles. Muller.

Chicago Style (17th ed.) Citation

Kelsey, Kenneth. A Third Book of Number Puzzles. London: Muller, 1984.

MLA (8th ed.) Citation

Kelsey, Kenneth. A Third Book of Number Puzzles. Muller, 1984.

Warning: These citations may not always be 100% accurate.