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