Duckworth, M. (1999). Countdown to first certificate. Oxford: Oxford University Press.
シカゴスタイル引用形Duckworth, Michael. Countdown to First Certificate. Oxford: Oxford University Press, 1999.
MLA引用形式Duckworth, Michael. Countdown to First Certificate. Oxford: Oxford University Press, 1999.
警告: この引用は必ずしも正確ではありません.