APA Style

Wong-Heng, S, S. (1999). Secondary One Environment and People : workbook 1A (normal) ; physical and human lanscapes . Singapore: The Educational Pub. House.

MLA Style

Wong-Heng, San, San,. "Secondary One Environment and People : workbook 1A (normal) ; physical and human lanscapes". Singapore: The Educational Pub. House, 1999. Text.