Enid Blyton. (1957). The Secret Seven Mystery: Secret Seven Mystery. Hodder Children's Books.
Citazione stile Chigago Style (17a edizione)Enid Blyton. The Secret Seven Mystery: Secret Seven Mystery. Great Britain: Hodder Children's Books, 1957.
Citatione MLA (9a ed.)Enid Blyton. The Secret Seven Mystery: Secret Seven Mystery. Hodder Children's Books, 1957.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.