Christophersen, P. (1939). The articles: A study of their theory and use in English. E. Munksgaard.
Lua i Stíl Chicago (17ú heag.)Christophersen, Paul. The Articles: A Study of Their Theory and Use in English. Copenhagen: E. Munksgaard, 1939.
Lua MLA (8ú heag.)Christophersen, Paul. The Articles: A Study of Their Theory and Use in English. E. Munksgaard, 1939.
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