Gaya APA
Heyworth, R, M. (2007).
Science in focus physics 'o' level 2nd edition theory workbook .
Singapore:
Pearson Longman.
Gaya MLA
Heyworth, Rex, M.
"Science in focus physics 'o' level 2nd edition theory workbook".
Singapore:
Pearson Longman,
2007.
Text.