diff --git a/有趣的4/readme.md b/有趣的4/readme.md
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-
+[什么是白皮书、蓝皮书、红皮书、黄皮书、绿皮书？ ](https://www.sohu.com/a/472589858_120296460)
 
   * [德勤中国研究《月度经济概览》](https://www2.deloitte.com/cn/zh/pages/about-deloitte/articles/deloitte-research-monthly-report.html)
   * [2023中国消费者洞察 与市场展望白皮书](https://www2.deloitte.com/content/dam/Deloitte/cn/Documents/consumer-business/deloitte-cn-cb-consumer-insight-zh-230118.pdf)