(1992). The penguin spelling dictionary. Bloomsbury Books;.
Chicago Style (17th ed.) ZitazioaThe Penguin Spelling Dictionary. London: Bloomsbury Books;, 1992.
MLA (9th ed.) ZitazioaThe Penguin Spelling Dictionary. Bloomsbury Books;, 1992.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.