Tay, B. (2007). Biology InsightsO Level Theory Workbook [teachers edition]Beverly Tay. Pearson Longman.
Chicago-viite (17. p.)Tay, Beverly. Biology InsightsO Level Theory Workbook [teachers Edition]Beverly Tay. Pearson Longman, 2007.
MLA-viite (8. p.)Tay, Beverly. Biology InsightsO Level Theory Workbook [teachers Edition]Beverly Tay. Pearson Longman, 2007.
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