Russell Punter. (2019). "Chilly Little Penguin (First Reading Level 2) [Paperback] [Jan 01, 2010] NILL". Usborne.
Chicago-viite (17. p.)Russell Punter. "Chilly Little Penguin (First Reading Level 2) [Paperback] [Jan 01, 2010] NILL". Usborne, 2019.
MLA-viite (9. p.)Russell Punter. "Chilly Little Penguin (First Reading Level 2) [Paperback] [Jan 01, 2010] NILL". Usborne, 2019.
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