罗文 & 詹森. (2018). 如果没有钱，物物交换也不错！: Let's trade:a book about bartering. 清华大学出版社.
Chicago Style (17th ed.) Citation罗文 and 詹森. 如果没有钱，物物交换也不错！: Let's Trade:a Book About Bartering. 清华大学出版社, 2018.
MLA (8th ed.) Citation罗文 and 詹森. 如果没有钱，物物交换也不错！: Let's Trade:a Book About Bartering. 清华大学出版社, 2018.
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