APA Citation

(1989). Practice and reinforcement: (Blue level). New York: Mc Dougal, Littell & Company.

Trích dẫn kiểu Chicago

Practice and Reinforcement: (Blue Level). New York: Mc Dougal, Littell & Company, 1989.

MLA Citation

Practice and Reinforcement: (Blue Level). New York: Mc Dougal, Littell & Company, 1989.

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