Enid Blyton. (1957). The Secret Seven Mystery: Secret Seven Mystery. Hodder Children's Books.
Chicago-viite (17. p.)Enid Blyton. The Secret Seven Mystery: Secret Seven Mystery. Great Britain: Hodder Children's Books, 1957.
MLA-viite (9. p.)Enid Blyton. The Secret Seven Mystery: Secret Seven Mystery. Hodder Children's Books, 1957.
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