Johnston, O. (2006). New Opportunities; education for life: Elementary language powerbook. Longman.
Chicago-viite (17. p.)Johnston, Olivia. New Opportunities; Education for Life: Elementary Language Powerbook. England: Longman, 2006.
MLA-viite (9. p.)Johnston, Olivia. New Opportunities; Education for Life: Elementary Language Powerbook. Longman, 2006.
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