APA (7th ed.) Citation

Lock, N. D. Time tests: Mental maths. Ladybird Book Ltd.

Chicago Style (17th ed.) Citation

Lock, Norman D. Time Tests: Mental Maths. London: Ladybird Book Ltd.

MLA (9th ed.) Citation

Lock, Norman D. Time Tests: Mental Maths. Ladybird Book Ltd.

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