Gaya APA

Service, E, T. (2021). Official TOEFL IBT Tests Volume 2 = 托福考试官方真题集 (First). Beijing (北京市): 群言出版社.

Gaya MLA

Service, Educational, Testing. "Official TOEFL IBT Tests Volume 2 = 托福考试官方真题集". First Beijing (北京市): 群言出版社, 2021. Text.