Webster, G. C. (1958). Nitrogen metabolism in plants. Harper & Row.
Chicago Style aipamenaWebster, George C. Nitrogen Metabolism in Plants. Newyork: Harper & Row, 1958.
MLA aipamenaWebster, George C. Nitrogen Metabolism in Plants. Harper & Row, 1958.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.