Gaya APA

Keng, D, L, T. (2001). Strategies To Solve Thinking Problems in Maths 1 (Cet. 1). Singapore: Educational Publishing House.

Gaya MLA

Keng, Dr, Lim, Tock. "Strategies To Solve Thinking Problems in Maths 1". Cet. 1 Singapore: Educational Publishing House, 2001. Text.