Citazione Stile APA (7a Edizione)

Writing Improvement Project. (1977). Building English skills. McDougal, Littell & Company.

Citazione stile Chigago Style (17a edizione)

Writing Improvement Project. Building English Skills. Evanston, Illinois: McDougal, Littell & Company, 1977.

Citatione MLA (9a ed.)

Writing Improvement Project. Building English Skills. McDougal, Littell & Company, 1977.