APA (7th ed.) Zitazioa
Chesterton, G. K. (1958). Essays and poems. Penguin books.
Chicago Style (17th ed.) Zitazioa
Chesterton, Gilbert. Keith. Essays and Poems. Penguin books, 1958.
MLA (9th ed.) Zitazioa
Chesterton, Gilbert. Keith. Essays and Poems. Penguin books, 1958.
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