Writing Improvement Project. (1977). Building English skills. McDougal, Littell & Company.
Chicagoスタイル(17版)引用形式Writing Improvement Project. Building English Skills. Evanston, Illinois: McDougal, Littell & Company, 1977.
MLA(9版)引用形式Writing Improvement Project. Building English Skills. McDougal, Littell & Company, 1977.
警告: この引用は必ずしも正確ではありません.