Gaya APA

PGDE, J, C, B. (2007). 100 Challenging Maths Word Problems Complete with Solutions Book 4 (1). Singapore: SAP.

Gaya MLA

PGDE, Joylynn, Cheng,, BA,. "100 Challenging Maths Word Problems Complete with Solutions Book 4". 1 Singapore: SAP, 2007. Print.