Gaya APA
Heyworth, R, M., Briggs, J, G, R. (2007).
Science In Focus Chemistry 'O' Level (Kedua).
Singapura:
Pearson Longman.
Gaya MLA
Heyworth, Rex, M.., Briggs, J., G., R..
"Science In Focus Chemistry 'O' Level".
Kedua
Singapura:
Pearson Longman,
2007.
Text.